PLATING APPARATUS, PLATING METHOD AND RECORDING MEDIUM

A plating apparatus can suppress a time period during which a plating liquid is used in a plating from being reduced. In the plating apparatus 1, after a plating liquid supply unit 53 supplies, to a substrate W1, a plating liquid which exerts a preset plating performance within a preset concentration range and which has an initial temperature adjusted to be lower than a preset plating temperature; and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range, a plating liquid heating unit 63 heats the plating liquid supplied to the substrate W1 to the preset plating temperature.

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Description
CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Japanese Patent Application No. 2015-212218 filed on Oct. 28, 2015, the entire disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The embodiments described herein pertain generally to a plating apparatus and a plating method. Further, the embodiments also relate to a recording medium having stored thereon a program for performing the plating method.

BACKGROUND

A plating liquid exerts a preset plating performance within a preset concentration range. When initially preparing the plating liquid in a plating bath, the plating liquid is adjusted to have the preset concentration range where the preset plating performance is achieved from the beginning. Then, during a plating, the concentration of the plating liquid is regulated to the preset concentration range where the preset plating performance is achieved. Patent Document 1 discloses a concentration management method and a concentration management system for a plating liquid.

Patent Document 2 describes a batch type plating apparatus. In the batch type plating apparatus, a plating liquid adjusted to have a preset concentration range where a preset plating performance can be achieved is initially prepared in a plating bath, and the plating upon a multiple number of substrates are performed in the plating bath at the same time. If the concentration of the plating liquid is decreased as a plating component in the plating liquid is consumed through the plating, the plating component is supplemented, and the plating is repeatedly performed within the plating bath. In the batch type plating apparatus, moisture is evaporated from the plating liquid in the plating bath. Since, however, the amount of the plating liquid in the plating bath is large, the decrease of the concentration of the plating liquid caused by the consumption of the plating component is more dominant than an increase of the concentration of the plating liquid caused by the evaporation of the moisture. Thus, the concentration of plating liquid in the plating bath tends to be decreased.

Patent Document 3 describes a single-substrate type plating apparatus. In the single-substrate type plating apparatus, a plating liquid which is adjusted to have a preset concentration range where a preset plating performance is achieved is supplied to a single sheet of substrate, and a plating of the single sheet of substrate is performed. The amount of the plating liquid supplied to the single sheet of substrate is much smaller than the amount of the plating liquid in the plating bath in the batch type plating apparatus. Thus, the increase of the concentration of the plating liquid caused by the evaporation of the moisture is more dominant than the decrease of the concentration of the plating liquid caused by the consumption of the plating component, so that the concentration of the plating liquid supplied to the single sheet of substrate tends to be increased.

Patent Document 1: Japanese Patent Laid-open Publication No. 2003-253453

Patent Document 2: Japanese Patent Laid-open Publication No. 2013-104118

Patent Document 3: Japanese Patent Laid-open Publication No. 2013-112845

In the single-substrate type processing apparatus, after a plating liquid having an initial temperature adjusted to be below a preset plating temperature and an initial concentration adjusted to be in a preset concentration range where a preset plating performance is achieved is supplied to a single sheet of substrate, the supplied plating liquid is heated to the preset plating temperature, and a plating is performed with the plating liquid which is heated to the preset plating temperature. In this case, during a time period before a temperature of the plating liquid reaches the preset plating temperature, a plating component in the plating liquid is hardly consumed, whereas moisture in the plating liquid is evaporated. As a result, the concentration of the plating liquid is increased. After the temperature of the plating liquid reaches the preset plating temperature, the plating component in the plating liquid is consumed. Since, however, the heating of the plating liquid is continued, the concentration of the plating liquid is increased. That is to say, since the increase of the concentration of the plating liquid caused by the evaporation of the moisture in the plating liquid is more dominant than the decrease of the concentration of the plating liquid caused by the consumption of the plating component in the plating liquid, the concentration of the plating liquid increases even after the temperature of the plating liquid reaches the preset plating temperature. The plating liquid can be used until its concentration reaches an upper limit of the preset concentration range. Since, however, the concentration of the plating liquid is already increased at a time when the temperature of the plating liquid has reached the preset plating temperature, a time period before the concentration of the plating liquid reaches the upper limit of the preset concentration range, that is, a time period during which the plating liquid can be used in the plating is shortened.

SUMMARY

In view of the foregoing, exemplary embodiments provide a plating apparatus and a plating method capable of suppressing a time period during which a plating liquid can be used in a plating from being reduced. Further, the exemplary embodiments also provide a recording medium having stored thereon a program for implementing this plating method.

The present disclosure includes following exemplary embodiments.

(1) A plating apparatus having a plating device configured to perform a plating on a substrate at a preset plating temperature; and a controller configured to control an operation of the plating device,

wherein the plating device comprises:

a plating liquid supply unit configured to supply, to the substrate, a plating liquid which allowed to exert a preset plating performance within a preset concentration range; and

    • a plating liquid heating unit configured to heat the plating liquid supplied to the substrate to the preset plating temperature,
    • wherein the plating liquid supplied to the substrate from the plating liquid supply unit has an initial temperature adjusted to be lower than the preset plating temperature, and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature while being heated by the plating liquid heating unit is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range, and

the controller controls the plating liquid supply unit and the plating liquid heating unit to perform, by supplying a preset amount of the plating liquid to the substrate a single time and heating the supplied plating liquid to the preset plating temperature, the plating with the plating liquid heated to the preset plating temperature.

(2) The plating apparatus as described in (1),

wherein the initial concentration is adjusted such that the concentration of the plating liquid at the moment when the temperature of the plating liquid has reached the preset plating temperature is close to the lower limit of the preset concentration range.

(3) The plating apparatus as described in (1) or (2),

wherein the initial concentration is adjusted to be lower than the lower limit of the preset concentration range.

(4) The plating apparatus as described in any one of (1) to (3),

wherein the plating device is equipped with a top plate disposed above the substrate, and

when the plating liquid supplied to the substrate is heated by the plating liquid heating unit, a space in which vapor generated from the plating liquid supplied to the substrate stays is formed between the substrate and the top plate.

(5) A plating method of performing a plating on a substrate at a preset plating temperature, the plating method comprising:

a plating liquid supplying process of supplying, to the substrate, a plating liquid which exerts a preset plating performance within a preset concentration range and which has an initial temperature adjusted to be lower than the preset plating temperature; and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range; and

a plating liquid heating process of heating the plating liquid supplied to the substrate to the preset plating temperature,

wherein a preset amount of the plating liquid is supplied to the substrate a single time in the plating liquid supplying process, and

in the plating liquid heating process, the plating liquid supplied in the plating liquid supplying process is heated to the preset plating temperature, and the plating is performed with the plating liquid heated to the preset plating temperature.

(6) The plating method as described in (5),

wherein the initial concentration is adjusted such that the concentration of the plating liquid at the moment when the temperature of the plating liquid has reached the preset plating temperature is close to the lower limit of the preset concentration range.

(7) The plating method as described in (5) or (6),

wherein the initial concentration is adjusted to be lower than the lower limit of the preset concentration range.

(8) The plating method as described in any one of (5) to (7),

wherein the plating liquid heating process is performed in a state where a space in which vapor generated from the plating liquid supplied to the substrate stays is formed between the substrate and a top plate disposed above the substrate.

(9) A computer-readable recording medium having stored thereon computer-executable instructions that, in response to execution, cause a plating apparatus to perform a plating method as described in any one of (5) to (8).

According to the exemplary embodiments as stated above, it is possible to provide a plating apparatus and a plating method capable of suppressing the time period during which the plating with the plating liquid is performed from being reduced. The exemplary embodiments also provide a recording medium having stored thereon a computer-executable program for implementing this plating method.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the detailed description that follows, embodiments are described as illustrations only since various changes and modifications will become apparent to those skilled in the art from the following detailed description. The use of the same reference numbers in different figures indicates similar or identical items.

FIG. 1 is a schematic diagram illustrating a configuration of a plating apparatus according to an exemplary embodiment;

FIG. 2 is a schematic plan view illustrating a configuration of a plating unit included in the plating apparatus shown in FIG. 1; and

FIG. 3 is a schematic cross sectional view illustrating a configuration of a plating device included in the plating unit shown in FIG. 2.

 DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part of the description. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Furthermore, unless otherwise noted, the description of each successive drawing may reference features from one or more of the previous drawings to provide clearer context and a more substantive explanation of the current exemplary embodiment. Still, the exemplary embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings, may be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

<Configuration of Plating Apparatus>

Referring to FIG. 1, a configuration of a plating apparatus according to an exemplary embodiment will be explained. FIG. 1 is a schematic diagram illustrating the configuration of the plating apparatus according to the exemplary embodiment.

As depicted in FIG. 1, the plating apparatus 1 according to the exemplary embodiment includes a plating unit 2 and a controller 3 configured to control an operation of the plating unit 2.

The plating unit 2 is configured to perform various processings on a substrate. The various processings performed by the plating unit 2 will be described later.

The controller 3 is implemented by, for example, a computer, and includes an operation controller and a storage unit. The operation controller is implemented by, for example, a CPU (Central Processing Unit) and is configured to control the operation of the plating unit 2 by reading and executing a program stored in the storage unit. The storage unit is implemented by a storage device such as, but not limited to, a RAM (Random Access Memory), a ROM (Read Only Memory) or a hard disk, and stores thereon a program for controlling various processings performed in the plating unit 2. Further, the program may be recorded in a computer-readable recording medium, or may be installed from the recording medium to the storage unit. The computer-readable recording medium may be, for example, a hard disc (HD), a flexible disc (FD), a compact disc (CD), a magnet optical disc (MO), or a memory card. The recording medium has stored thereon a program that, when executed by a computer for controlling an operation of the plating apparatus 1, causes the plating apparatus 1 to perform a plating method to be described later under the control of the computer.

<Configuration of Plating Unit>

Referring to FIG. 2, a configuration of the plating unit 2 will be discussed. FIG. 2 is a schematic plan view illustrating the configuration of the plating unit 2. In FIG. 2, dashed lines indicate substrates.

The plating unit 2 includes a carry-in/out station 21; and a processing station 22 provided adjacent to the carry-in/out station 21.

The carry-in/out station 21 includes a placing section 211; and a transfer section 212 provided adjacent to the placing section 211.

In the placing section 211, a plurality of transfer containers (hereinafter, referred to as “carriers C”) is placed to accommodate a plurality of substrates horizontally.

The transfer section 212 is provided with a transfer device 213 and a delivery unit 214. The transfer device 213 is provided with a holding mechanism configured to hold a substrate. The transfer device 213 is configured to be movable horizontally and vertically and pivotable around a vertical axis.

The processing station 22 includes plating devices 5. In the present exemplary embodiment, the number of the plating devices 5 provided in the processing station 22 may be two or more, but it is also possible to provide only one plating device 5. The plating devices 5 are arranged at both side of a transfer path 221 which is extended in a preset direction.

The transfer path 221 is provided with a transfer device 222. The transfer device 222 includes a holding mechanism configured to hold a substrate, and is configured to be movable horizontally and vertically and pivotable around a vertical axis.

In the following description, a substrate before being loaded into the plating device 5 will be referred to as “substrate W0”; a substrate which has been loaded into the plating device 5 and is yet to be unloaded from the plating device 5 will be referred to as “substrate W1”; and a substrate after being unloaded from the plating device 5 will be referred to as “W2.”

In the plating unit 2, the transfer device 213 of the carry-in/out station 21 is configured to transfer the substrates W0 and W2 between the carriers C and the delivery unit 214. To elaborate, the transfer device 213 takes out the substrate W0 from the carrier C placed in the placing section 211, and then, places the substrate W0 in the delivery unit 214. Further, the transfer device 213 takes out the substrate W2 which is placed in the delivery unit 214 by the transfer device 222 of the processing station 22, and then, accommodates the substrate W2 in the carrier C of the placing section 211.

In the plating unit 2, the transfer device 222 of the processing station 22 is configured to transfer the substrates W0 and W2 between the delivery unit 214 and the plating device 5 and between the plating device 5 and the delivery unit 214. To elaborate, the transfer device 222 takes out the substrate W0 placed in the delivery unit 214 and carries the substrate W0 into the plating device 5. Further, the transfer device 222 takes out the substrate W2 from the plating device 5 and places the substrate W2 in the delivery unit 214.

<Configuration of Plating Device>

Referring to FIG. 3, a configuration of the plating device 5 will be explained. FIG. 3 is a schematic cross sectional view illustrating the configuration of the plating device 5.

The plating device 5 is configured to perform a plating on a substrate W1 at a preset plating temperature. The plating performed by the plating device 5 is an electroless plating. Here, a substrate processing performed by the plating device 5 is not particularly limited as long as it includes the plating. That is, the substrate processing performed by the plating device 5 may include other processings than the plating. In the present exemplary embodiment, the substrate processing performed by the plating device 5 includes the plating and a pre-processing which is performed prior to the plating.

The plating device 5 includes a chamber 51, and is configured to perform a substrate processing including the plating within the chamber 51.

The plating device 5 is provided with a substrate holding unit 52 configured to hold the substrate W1. The substrate holding unit 52 includes a rotation shaft 521 extended in a vertical direction within the chamber 51; a turntable 522 provided at an upper end portion of the rotation shaft 521; a chuck 523 provided on an outer peripheral portion of a top surface of the turntable 522 and configured to support an edge portion of the substrate W1; and a driving unit 524 configured to rotate the rotation shaft 521.

The substrate W1 is supported by the chuck 523 to be horizontally held on the turntable 522 while being slightly spaced apart from the top surface of the turntable 522. In the present exemplary embodiment, a mechanism of holding the substrate W1 by the substrate holding unit 52 is of a so-called mechanical chuck type in which the edge portion of the substrate W1 is held by the chuck 523 which is configured to be movable. However, a so-called vacuum chuck type of vacuum attracting a rear surface of the substrate W1 may be used instead.

A base end portion of the rotation shaft 521 is rotatably supported by the driving unit 524, and a leading end portion of the rotation shaft 521 sustains the turntable 522 horizontally. If the rotation shaft 521 is rotated, the turntable 522 placed on the upper end portion of the rotation shaft 521 is rotated, and, as a result, the substrate W1 which is held on the turntable 522 by the chuck 523 is also rotated. The controller 3 controls the driving unit 524 to adjust, e.g., a rotation timing, a rotational speed and a rotation time of the substrate W1.

The plating device 5 includes a plating liquid supply unit 53 configured to supply a plating liquid M1 onto the substrate W1 which is held by the substrate holding unit 52. The plating liquid supply unit 53 is equipped with a nozzle 531 configured to discharge the plating liquid M1 toward the substrate W1 held by the substrate holding unit 52; and a plating liquid supply source 532 configured to supply the plating liquid M1 to the nozzle 531. The plating liquid M1 is stored in a tank of the plating liquid supply source 532, and the plating liquid M1 is supplied into the nozzle 531 from the plating liquid supply source 532 through a supply passageway 534 which is equipped with a flow rate controller such as a valve 533. The controller 3 controls, for example, a supply timing and a supply amount of the plating liquid M1 by controlling the plating liquid supply unit 53.

The plating liquid M1 is an autocatalytic (reduction) plating liquid for electroless plating. The plating liquid M1 contains a metal ion such as a cobalt (Co) ion, a nickel (Ni) ion, a tungsten (W) ion, a copper (Cu) ion, a palladium (Pd) ion or a gold (Au) ion; and a reducing agent such as hypophosphorous acid or dimethylamineborane. Further, in the autocatalytic (reduction) electroless plating, the metal ion in the plating liquid M1 is reduced by the electrons emitted in an oxidation reaction of the reducing agent in the plating liquid M1 and is precipitated as a metal, so that a metal film (plating film) is formed. The plating liquid M1 may further contain an additive or the like. The metal film (plating film) formed by the plating with the plating liquid M1 may be, by way of non-limiting example, CoWB, CoB, CoWP, CoWBP, NiWB, NiB, NiWP, NiWBP, or the like. P in the metal film (plating film) is originated from the reducing agent (e.g., hypophosphorous acid) containing P, and B in the plating film is originated from the reducing agent (e.g., dimethylamineborane) containing B.

The plating liquid M1 supplied from the plating liquid supply unit 53 (that is, the plating liquid M1 stored in the tank of the plating liquid supply source 532) is a plating liquid which conducts a preset plating performance within a preset concentration range. It is determined, whether the plating liquid M1 exhibits the preset plating performance, based on whether a metal film (plating film) having a preset property (e.g., a thickness of 30 nm to 100 nm) is obtained when an electroless plating is performed by using a preset amount of the plating liquid M1 at a preset plating temperature for a predetermined time.

The plating liquid M1 contains a multiple number of components. In order for the plating liquid M1 to provide the preset plating performance, a concentration of each component needs to be within a predetermined concentration range. That is, each of the components contained in the plating liquid M1 has a predetermined concentration range which is required for the plating liquid M1 to exerts the preset plating performance. The predetermined concentration range of each component is appropriately determined based on a composition of the plating liquid M1, and the like. Among all the components contained in the plating liquid M1, a concentration of a component which has a predetermined concentration range having a smallest difference between an upper limit and a lower limit is defined as a “concentration of the plating liquid M1.” To elaborate, if the component having the smallest difference between the upper limit and the lower limit of the predetermined concentration range is a metal ion forming the metal film (plating film), the concentration of the metal ion is defined as “concentration of the plating liquid M1” and the predetermined concentration range of the metal ion is defined as the “preset concentration range of the plating liquid M1.” If the component having the smallest difference between the upper limit and the lower limit of the predetermined concentration range is a reducing agent, on the other hand, the concentration of the reducing agent is defined as “concentration of the plating liquid M1” and the predetermined concentration range of the reducing agent is defined as the “preset concentration range of the plating liquid M1.” Here, the preset concentration range of the plating liquid M1 is expressed as CL (%)˜CH (%).

A concentration and a temperature of the plating liquid M1 supplied from the plating liquid supply unit 53 (that is, the plating liquid M1 stored in the tank of the plating liquid supply source 532) is referred to as “initial concentration” and “initial temperature,” and are distinguished from a concentration and a temperature of the plating liquid M1 after being supplied from the plating liquid supply unit 53 to the substrate W1 held by the substrate holding unit 52.

After the plating liquid M1 is supplied from the plating liquid supply unit 53 onto the substrate W1 held by the substrate holding unit 52, the concentration and the temperature of the plating liquid M1 are changed. The concentration of the plating liquid M1 is changed as moisture in the plating liquid M1 evaporates and/or as a plating component in the plating liquid M1 is consumed. The temperature of the plating liquid M1 is changed as the plating liquid M1 is heated by a plating liquid heating unit 63. To be specific, during a period from when the plating liquid M1 is supplied from the plating liquid supply unit 53 to the substrate W1 held by the substrate holding unit 52 to when the supplied plating liquid M1 reaches the preset plating temperature while being heated by the plating liquid heating unit 63, the plating component in the plating liquid M1 is hardly consumed, whereas the moisture in the plating liquid M1 is evaporated. Thus, during this period, the concentration of the plating liquid M1 is increased. After the temperature of the plating liquid M1 has reached the preset plating temperature, since the heating by the plating liquid heating unit 63 is continued, the concentration of the plating liquid M1 is still increased, though the plating component in the plating liquid M1 is consumed. That is, since an increase of the concentration of the plating liquid M1 caused by the evaporation of the moisture in the plating liquid M1 is more dominant than a decrease of the concentration of the plating liquid M1 caused by the consumption of the plating component in the plating liquid M1, the concentration of the plating liquid M1 is kept being increased even after the temperature of the plating liquid M1 has reached the preset plating temperature, and reaches the upper limit (i.e., CH (%)) of the preset concentration range, shortly.

The initial temperature of the plating liquid M1 is adjusted to be below the preset plating temperature. The plating temperature is a temperature where a plating reaction (a reaction in which the metal ion in the plating liquid M1 is reduced by electrons emitted through an oxidation reaction of the reducing agent in the plating liquid M1 and is precipitated as a metal) progresses. For example, the plating temperature may be, but not limited to, 60° C. to 70° C. The initial temperature of the plating liquid M1 is, by way of non-limiting example, 23° C. to 27° C.

The initial concentration of the plating liquid M1 is adjusted such that the concentration of the plating liquid M1 at the moment when the temperature of the plating liquid M1 has reached the preset plating temperature is equal to or higher than the lower limit (i.e., CL (%)) of the preset concentration range and equal to or lower than a median value (i.e., (CL+CH)/2) of the preset concentration range.

Assume that the initial concentration of the plating liquid M1 is X (%); the amount of the plating liquid M1 supplied from the plating liquid supply unit 53 to the substrate W1 held by the substrate holding unit 52 is Y (mL) (the plating liquid supply unit 53 does not supplement new plating liquid M1 until the plating with the plating liquid M1 is completed after the preset amount of the corresponding plating liquid M1 is once supplied); and the amount of the moisture evaporated from the supplied plating liquid M1 during the period from when the plating liquid M1 is supplied from the plating liquid supply unit 53 to the substrate W1 held by the substrate holding unit 52 to when the temperature of the supplied plating liquid M1 has reached the preset plating temperature while being heated by the plating liquid heating unit 63 is Z (mL). The concentration (%) of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature is expressed as (X×Y)/(Y−Z). Since the concentration (%) of the plating liquid M1 at the time when it has reached the preset plating temperature is equal to or higher than CL and equal to or lower than (CL+CH)/2, an expression of CL≦(X×Y)/(Y−Z)≦(CL+CH)/2 is established. By modifying this expression, the initial concentration X (%) of the plating liquid M1 is expressed as CL(1−Z/Y)≦×≦(CL+CH)(1−Z/Y)/2.

Since Z/Y is less than 1, a lower limit CL(1−Z/Y) of the initial concentration (%) of the plating liquid M1 is less than CL.

When there is established a relationship of Z/Y=1−2CL/(CL+CH), an upper limit (CL+CH)(1−Z/Y)/2 of the initial concentration (%) of the plating liquid M1 is equal to CL.

When there is established a relationship of Z/Y>1−2CL/(CL+CH), the upper limit (CL+CH)(1−Z/Y)/2 of the initial concentration (%) of the plating liquid M1 is less than CL.

When there is established a relationship of Z/Y<1−2CL/(CL+CH), the upper limit (CL+CH)(1−Z/Y)/2 of the initial concentration (%) of the plating liquid M1 exceeds CL.

Accordingly, though the lower limit of the initial concentration (%) of the plating liquid M1 is always less than CL, the upper limit of the initial concentration (%) of the plating liquid M1 may be less than CL, equal to CL or exceed CL.

As the concentration of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature is closer to the lower limit (i.e., CL (%)) of the preset concentration range, a time period taken until the concentration of the plating liquid M1 reaches the upper limit (i.e., CH (%)) of the preset concentration range, that is, a time period during which the plating liquid M1 can be used for the plating is lengthened. In this aspect, the concentration of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature is desirably set to be near the lower limit (i.e., CL(%)) of the preset concentration range, and, more desirably, set to be the lower limit (i.e., CL(%)) of the preset concentration range.

The concentration of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature is larger than the initial concentration thereof. Thus, if the initial concentration (%) of the plating liquid M1 is equal to or higher than CL, it may be difficult to adjust the concentration of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature to be close to the lower limit (i.e., CL (%)) of the preset concentration range. Therefore, it is desirable that the initial concentration (%) of the plating liquid M1 is less than the lower limit (i.e., CL (%)) of the preset concentration range.

After supplying the preset amount of the plating liquid M1 a single time, the plating liquid supply unit 53 does not supply new plating liquid M1 until the plating with the supplied plating liquid M1 is completed. Desirably, the preset amount of the plating liquid M1 supplied from the plating liquid supply unit 53 at the singe time is 20 mL to 200 mL and, more desirably, 30 mL to 100 mL in case that the substrate W1 has a diameter of 300 mm. The plating on a single sheet of substrate W1 is performed with the preset amount of the plating liquid M1 which is supplied one time from the plating liquid supply unit 53. That is, the plating on the single sheet of substrate W1 is begun at the time when the plating liquid M1 supplied to the substrate W1 reaches the plating temperature and is finished at the time when the plating liquid M1 is drained from the substrate W1. Further, the plating liquid M1 is drained from the substrate W1 before the concentration of the plating liquid M1 reaches the upper limit (i.e., CH (%)) of the preset concentration range. Since the temperature of the plating liquid M1 supplied from the plating liquid supply unit 53 is lower than the preset plating temperature, the plating is not begun or, even if begun, progresses very slowly at the time when the plating liquid M1 is supplied from the plating liquid supply unit 53 to the substrate W1 held by the substrate holding unit 52. After the plating liquid M1 is supplied from the plating liquid supply unit 53 to the substrate W1 which is held by the substrate holding unit 52, the plating is begun at the time when the temperature of the supplied plating liquid M1 reaches the preset plating temperature while being heated by the plating liquid heating unit 63. During the plating, the temperature of the plating liquid M1 is maintained at the preset plating temperature by the plating liquid heating unit 63. Accordingly, the plating is performed with the plating liquid M1 which is heated to the preset plating temperature.

A circulation passageway 537 provided with a pump 535 and a heating unit 536 is connected to the tank of the plating liquid supply source 532. The plating liquid M1 in the tank is heated to a storage temperature while being circulated through the circulation passageway 537. Here, the “storage temperature” refers to a temperature higher than a room temperature and lower than a temperature (plating temperature) where the precipitation of the metal ion in the plating liquid M1 progresses through a self-reaction. In the present exemplary embodiment, though the plating liquid M1 in the tank is heated to the storage temperature, the plating liquid M1 in the tank may be kept at a room temperature. According to the exemplary embodiment, evaporation of the components, deactivation of the reducing agent in the plating liquid M1 or the like, which might occur in case where the plating liquid M1 is heated to the plating temperature within the tank, can be suppressed. Therefore, a lifetime of the plating liquid M1 can be lengthened.

A chemical liquid L1 containing various components of the plating liquid M1 is supplied into the tank of the plating liquid supply source 532 from a chemical liquid supply source 538a which stores the chemical liquid L1 through a supply passageway 538c which is equipped with a flow rate controller 538b such as a valve. Further, a diluent liquid L2 which dilutes the chemical liquid L1 is supplied into the tank of the plating liquid supply source 532 from a diluent liquid supply source 539a which stores the diluent liquid L2 through a supply passageway 539c which is equipped with a flow rate controller 539b such as a valve. The diluent liquid L2 is, for example, pure water. The chemical liquid L1 supplied from the chemical liquid supply source 538a and the diluent liquid L2 supplied from the diluent liquid supply source 539a are mixed, so that the plating liquid M1 is prepared. At this time, a flow rate of the chemical liquid L1 is adjusted by the flow rate controller 538b and a flow rate of the diluent liquid L2 is adjusted by the flow rate controller 539b such that the concentration of the plating liquid M1 has the preset concentration.

In the present exemplary embodiment, though only one chemical liquid L1 containing all the components of the plating liquid M1 is used, it may be possible to use two or more chemical liquids each of which contains a part of the components of the plating liquid M1. Further, the components contained in each chemical liquid are adjusted such that the two or more chemical liquids contain all the components of the plating liquid M1 as a whole. When using the two or more chemical liquids each containing a part of the components of the plating liquid M1, the two or more chemical liquids are supplied into the tank of the plating liquid supply source 532 from corresponding two or more chemical liquid supply sources storing the respective chemical liquids through supply passageways each of which is equipped with flow rate controller such as a valve. As the respective chemical liquids supplied from the two or more chemical liquid supply sources and the diluent liquid L2 supplied from the diluent liquid supply source 539a are mixed in the tank, the plating liquid M1 is prepared. At this time, flow rates of the respective chemical liquids are adjusted by the corresponding flow rate controllers and the flow rate of the diluent liquid L2 is adjusted by the flow rate controller 539b such that the plating liquid M1 is allowed to have the preset concentration.

A degassing unit (not shown) configured to remove dissolved oxygen and dissolved hydrogen in the plating liquid M1 may be provided in the tank of the plating liquid supply source 532. The degassing unit is configured to supply an inert gas such as, but not limited to, a nitrogen gas into the tank and dissolve the inert gas such as the nitrogen gas in the plating liquid M1, so that the other gases such as the oxygen and the hydrogen previously dissolved in the plating liquid M1 may be discharged to the outside of the plating liquid M1. The gases such as the oxygen and the hydrogen discharged from the plating liquid M1 may be exhausted from the tank by an exhaust unit (not shown). The circulation passageway 537 may be provided with a filter (not shown). By providing the filter in the circulation passageway 537, various kinds of impurities contained in the plating liquid M1 can be removed. The circulation passageway 537 may be further provided with a monitoring unit (not shown) configured to monitor a characteristic of the plating liquid M1. The monitoring unit may be implemented by, for example, a temperature monitoring unit configured to monitor a temperature of the plating liquid M1, a pH monitoring unit configured to monitor a pH of the plating liquid M1, or the like.

The plating device 5 is equipped with a nozzle moving mechanism 54 configured to move the nozzle 531. The nozzle moving mechanism 54 includes an arm 541; a moving body 542 which is configured to be movable along the arm 541 and has a moving mechanism embedded therein; and a rotating/elevating mechanism 543 configured to rotate and move the arm 541 up and down. The nozzle 531 is provided at the moving body 542. The nozzle moving mechanism 54 is capable of moving the nozzle 531 between a position above a central portion of the substrate W1 held by the substrate holding unit 52 and a position above a peripheral portion of the substrate W1, and also capable of moving the nozzle 531 up to a stand-by position outside a cup 57 to be described later when viewed from the top. The controller 3 controls the nozzle moving mechanism 54 to adjust a moving timing, a moved position of the nozzle 531, and so forth.

The plating device 5 includes a catalyst solution supply unit 55a, a cleaning liquid supply unit 55b and a rinse liquid supply unit 55c configured to supply a catalyst solution N1, a cleaning liquid N2 and a rinse liquid N3 onto the substrate W1 held by the substrate holding unit 52, respectively. Further, it may be appropriately determined depending on the kind of the plating liquid M1 whether to provide the catalyst solution supply unit 55a. That is, depending on the kind of the plating liquid M1, the catalyst solution supply unit 55a may be omitted.

The catalyst solution supply unit 55a includes a nozzle 551a configured to discharge the catalyst solution N1 onto the substrate W1 held by the substrate holding unit 52; and a catalyst solution supply source 552a configured to supply the catalyst solution N1 to the nozzle 551a. The catalyst solution N1 is stored in a tank of the catalyst solution supply source 552a, and the catalyst solution N1 is supplied to the nozzle 551a from the catalyst solution supply source 552a through a supply passageway 554a which is provided with a flow rate controller such as a valve 553a. The controller 3 controls the catalyst solution supply unit 55a to adjust a supply timing of the catalyst solution N1, a supply amount thereof, and so forth.

The cleaning liquid supply unit 55b includes a nozzle 551b configured to discharge the cleaning liquid N2 onto the substrate W1 held by the substrate holding unit 52; and a cleaning liquid supply source 552b configured to supply the cleaning liquid N2 to the nozzle 551b. The cleaning liquid N2 is stored in a tank of the cleaning liquid supply source 552b, and the cleaning liquid N2 is supplied to the nozzle 551b from the cleaning liquid supply source 552b through a supply passageway 554b which is provided with a flow rate controller such as a valve 553b. The controller 3 controls the cleaning liquid supply unit 55b to adjust a supply timing of the cleaning liquid N2, a supply amount thereof, and so forth.

The rinse liquid supply unit 55c includes a nozzle 551c configured to discharge the rinse liquid N3 onto the substrate W1 held by the substrate holding unit 52; and a rinse liquid supply source 552c configured to supply the rinse liquid N3 to the nozzle 551c. The rinse liquid N3 is stored in a tank of the rinse liquid supply source 552c, and the rinse liquid N3 is supplied to the nozzle 551c from the rinse liquid supply source 552c through a supply passageway 554c which is provided with a flow rate controller such as a valve 553c. The controller 3 controls the rinse liquid supply unit 55c to adjust a supply timing of the rinse liquid N3, a supply amount thereof, and so forth.

The catalyst solution N1, the cleaning liquid N2 and the rinse liquid N3 are pre-treatment liquids for pre-processings that are performed prior to the plating with the plating liquid M1.

The catalyst solution N1 contains a metal ion (e.g., a palladium (Pd) ion, a platinum (Pt) ion, a gold (Au) ion, etc.) having catalytic activity to an oxidation reaction of the reducing agent in the plating liquid M1. In the electroless plating, in order to start precipitation of the metal ion in the plating liquid M1, an initial film surface (that is, plating target surface of substrate) needs to have sufficient catalytic activity to the oxidation reaction of the reducing agent in the plating liquid M1. Thus, depending on the kind of the plating liquid M1, it may be desirable to process the plating target surface of the substrate with the catalyst solution N1 and form a metal film having the catalytic activity on the plating target surface of the substrate before starting the plating with the plating liquid M1. It may be appropriately determined depending on the kind of the plating liquid M1 whether to perform the processing with the catalyst solution N1 before starting the plating. That is, depending on the kind of the plating liquid M1, the processing with the catalyst solution N1 may be omitted. The metal film having the catalytic activity is formed through a replacement reaction. In the replacement reaction, a metal forming the plating target surface of the substrate (e.g., copper in a copper wiring formed on the plating target surface of the substrate) serves as the reducing agent, and the metal ion (e.g., Pd ion) in the catalyst solution N1 is reduced to be precipitated on the plating target surface of the substrate.

As an example of the cleaning liquid N2, an organic acid such as a malic acid, a succinic acid, a citric acid or a malonic acid, or hydrofluoric acid (DHF) (aqueous solution of hydrogen fluoride) diluted to the extent that it does not corrode the plating target surface of the substrate may be used.

As an example of the rinse liquid N3, pure water may be used.

The plating device 5 includes a nozzle moving mechanism 56 configured to move the nozzles 551a to 551c. The nozzle moving mechanism 56 is equipped with an arm 561; a moving body 562 which is configured to be movable along the arm 561 and has a moving mechanism embedded therein; and a rotating/elevating mechanism 563 configured to rotate and move the arm 561 up and down. The nozzles 551a to 551c are provided at the moving body 562. The nozzle moving mechanism 56 is capable of moving the nozzles 551a to 551c between a position above the central portion of the substrate W1 held by the substrate holding unit 52 and a position above the peripheral portion of the substrate W1, and also capable of moving the nozzles 551a to 551c up to a stand-by position outside the cup 57 to be described later when viewed from the top. In the present exemplary embodiment, though the nozzles 551a to 551c are held by the common arm, they may be configured to be held by different arms and moved independently. The controller 3 controls the nozzle moving mechanism 56 to adjust moving timings, moved positions of the nozzles 551a to 551c, and so forth by controlling.

The plating device 5 is equipped with the cup 57 having drain openings 571a,571b and 571c. The cup 57 is disposed around the substrate holding unit 52, and is configured to collect various kinds of processing liquids (e.g., plating liquid, catalyst solution, cleaning liquid, rinse liquid, etc.) which are scattered from the substrate W1. The cup 57 is provided with an elevating mechanism 58 configured to move the cup 57 up and down; and liquid draining mechanisms 59a, 59b and 59c configured to collect and drain the various kinds of processing liquids scattered from the substrate W1 through the drain openings 571a,571b and 571c, respectively. By way of example, the plating liquid M1 scattered from the substrate W1 is drained from the liquid draining mechanism 59a; the catalyst solution N1 scattered from the substrate W1 is drained from the liquid draining mechanism 59b; and the cleaning liquid N2 and the rinse liquid N3 scattered from the substrate W1 are drained from the liquid draining mechanism 59c. The controller 3 controls the elevating mechanism 58 to adjust a moving timing, a moved position of the cup 57, and so forth.

The plating device 5 is also equipped with a top plate 61 disposed above the substrate W1 held by the substrate holding unit 52; and an elevating mechanism 62 configured to move the top plate 61 in a vertical direction and in a horizontal direction. The top plate 61 is disposed above the substrate W1 while being spaced apart from the substrate W1. When viewed from the top, the top plate 61 has a shape (e.g., a circular shape) corresponding to the shape of the substrate W1, and the size of the top plate 61 is adjusted to cover the substantially entire surface region of the substrate W1. The shape and the size of the top plate 61 are not particularly limited and can be appropriately modified as long as a space can be formed between the substrate W1 and the top plate 61. By way of example, when viewed from the top, the top plate 61 may have a rectangular shape or the like. Further, the top plate 61 is not provided with any through hole or opening which can serve a flow path of vapor which is generated from the plating liquid M1. The controller 3 controls the elevating mechanism 62 to adjust a moving timing, a moved position of the top plate 61, and so forth by controlling.

The top plate 61 is configured to be moved up and down by the elevating mechanism 62 independently from the cup 57. Accordingly, carrying-in and carrying-out of the substrate onto/from the substrate holding unit 52 can be facilitated.

The elevating mechanism 62 is configured to move the top plate 61 horizontally between a position where the top plate 61 covers the substantially entire surface region of the substrate W1 and a position where the top plate 61 does not cover the substantially entire surface region of the substrate W1. Further, the elevating mechanism 62 is capable of adjusting a distance between the substrate W1 and the top plate 61 (i.e., a volume of a space S formed between the substrate W1 and the top plate 61) by moving the top plate 61 in the vertical direction after moving the top plate 61 to the position where it covers the substantially entire surface region of the substrate W1. After the top plate 61 is horizontally moved to the position where it does not cover the substantially entire surface region of the substrate W1, the liquids are supplied from the various nozzles to the substrate W1 held by the substrate holing unit 52. Further, after the top plate 61 is moved to the position where it covers the substantially entire surface region of the substrate W1 and the distance between the substrate W1 and the top plate 61 (i.e., the volume of the space S formed between the substrate W1 and the top plate 61) is adjusted, the plating liquid M1 supplied to the substrate W1 is heated.

By adjusting the distance between the substrate W1 and the top plate 61 after moving the top plate 61 to the position where the top plate 61 covers the substantially entire surface region of the substrate W1, the space S is formed between the substrate W1 held by the substrate holding unit 52 and the top plate 61 disposed above the substrate W1. The space S is surrounded by the cup 57, but is not sealed by the cup 57 and the space S communicates with an external space (a space within the chamber 51). If the moisture in the plating liquid M1 supplied to the substrate W1 held by the substrate holding unit 52 is evaporated, the vapor generated from the plating liquid M1 is flown out into the external space after staying in the space S. Accordingly, the moisture in the plating liquid M1 supplied to the substrate W1 held by the substrate holding unit 52 is continuously evaporated. By adjusting the volume of the space S (e.g., the distance between the substrate W1 held by the substrate holding unit 52 and the top plate 61), an evaporation amount of the moisture from the plating liquid M1 can be adjusted. For example, by reducing the volume of the space S, the evaporation amount of the moisture from the plating liquid M1 can be reduced. Accordingly, a sharp increase of the concentration of the plating liquid M1 caused by the evaporation of the moisture can be suppressed. The moisture that stays in the space S serves as a heat medium when heating, by the plating liquid heating unit 63, the plating liquid M1 supplied onto the substrate W1 which is held by the substrate holding unit 52. The distance between the substrate W1 held by the substrate holding unit 52 and the top plate 61 is appropriately adjusted based on a set temperature of the top plate, a temperature of the plating liquid after being heated, a temperature rising rate of the plating liquid, an amount of the plating liquid on the substrate, and so forth.

The top plate 61 is equipped with the plating liquid heating unit 63 configured to heat the plating liquid M1 supplied onto the substrate W1 which is held by the substrate holding unit 52. Further, the substrate W1 held by the substrate holding unit 52 is also heated by the plating liquid heating unit 63. The plating liquid heating unit 63 includes a heater such as a lamp heater (e.g., a LED lamp heater) and a heating wire. In the present exemplary embodiment, the heater of the plating liquid heating unit 63 is embedded within the top plate 61. In the present exemplary embodiment, the plating liquid heating unit 63 heats the plating liquid M1 on the substrate W1 from above the substrate W1 held by the substrate holding unit 52. However, the plating liquid heating unit 63 may be configured to heat the plating liquid M1 on the substrate W1 from below the substrate W1 held by the substrate holding unit 52. In this case, the plating liquid M1 on the substrate W1 is heated by heating the substrate W1 held by the substrate holding unit 52. By way of example, the plating liquid heating unit 63 may be provided at the turntable 522 of the substrate holding unit 52. The controller 3 controls the plating liquid heating unit 63 to adjust a heating timing, a heating temperature, a heating time, and so forth.

<Plating Method>

Now, a plating method performed by the plating apparatus 1 will be discussed. The plating method performed by plating apparatus 1 includes a plating process of performing a plating on the substrate W1. The plating in the plating process is performed by the plating devices 5. An operation of the plating device 5 is controlled by the controller 3. The plating method performed by the plating apparatus 1 may further include other processes than the plating process.

First, a substrate carry-in process is performed. In the substrate carry-in process, the substrate W1 is carried into the plating device 5. The controller 3 controls the transfer device 213 to take out a substrate W0 from a carrier C placed in the placing section 211 and to place the taken substrate W0 in the delivery unit 214. Then, the controller 3 controls the transfer device 222 to take out the substrate W0 placed in the delivery unit 214 and to carry the taken substrate W0 into the plating device 5.

After the substrate carry-in process, a substrate holding process is performed. In the substrate holding process, the substrate W1 carried into the plating device 5 is held by the substrate holding unit 52. The controller 3 controls the elevating mechanism 58 to move the cup 57 down to a preset position, and also controls the elevating mechanism 62 to move the top plate 61 horizontally to the position where it does not cover the substantially entire surface region of the substrate W1. Accordingly, the transfer device 222 is allowed to access the substrate holding unit 52. The controller 3 controls the transfer device 222 to place the substrate W1 on the substrate holding unit 52. The substrate W1 is horizontally placed on the turntable 522 while its periphery portion is held by the chuck 523.

After the substrate holding process, the plating process is performed. The plating in the plating process is performed on the substrate W1 held by the substrate holding unit 52. The plating device 5 may perform a pretreatment process of pre-processing the substrate W1 before the plating process. The pretreatment process may include a cleaning process; and a first rinse process which is performed after the cleaning process. Further, the pretreatment process may also include a catalyst solution supplying process which is performed after the first rinse process. Furthermore, the pretreatment process may further include a second rinse process which is performed after the catalyst solution supplying process.

In the cleaning process, the substrate W1 held by the substrate holding unit 52 is cleaned. While rotating the substrate W1 held by the substrate holding unit 52 at a preset speed by controlling the driving unit 524, the controller 3 controls the cleaning liquid supply unit 55b to locate the nozzle 551b at a position above the substrate W1, and a cleaning liquid N2 is supplied onto the substrate W1 from the nozzle 551b. The cleaning liquid N2 supplied onto the substrate W1 is diffused on a surface of the substrate W1 by a centrifugal force which is generated as the substrate W1 is rotated. As a result, a deposit or the like adhering to the substrate W1 is removed from the substrate W1. The cleaning liquid N2 scattered from the substrate W1 is drained through the drain opening 571c of the cup 57 and the liquid draining mechanism 59c. When starting this cleaning process, the controller 3 controls the elevating mechanism 58 to adjust the position of the cup 57 such that the drain opening 571c of the cup 57 is located at a position where it faces a peripheral edge portion of the substrate W1.

In the first rinse process, the substrate W1 after being cleaned is rinsed. While rotating the substrate W1 held by the substrate holding unit 52 at a preset speed by controlling the driving unit 524, the controller 3 controls the rinse liquid supply unit 55c to locate the nozzle 551c at a position above the substrate W1, and a rinse liquid N3 is supplied onto the substrate W1 from the nozzle 551c. The rinse liquid N3 supplied onto the substrate W1 is diffused on the surface of the substrate W1 by a centrifugal force which is generated as the substrate W1 is rotated. As a result, the cleaning liquid N2 remaining on the substrate W1 is washed away. The rinse liquid N3 scattered from the substrate W1 is drained through the drain opening 571c of the cup 57 and the liquid draining mechanism 59c. When starting this first rinse process, the controller 3 controls the elevating mechanism 58 to adjust the position of the cup 57 such that the drain opening 571c of the cup 57 is located at a position where it faces the peripheral edge portion of the substrate W1.

In the catalyst solution supplying process, a metal film (catalyst layer) having catalytic activity is formed on the substrate W1 after being rinsed. While rotating the substrate W1 held by the substrate holding unit 52 at a preset speed by controlling the driving unit 524, the controller 3 controls the catalyst solution supply unit 55a to locate the nozzle 551a at a position above the substrate W1, and a catalyst solution N1 is supplied onto the substrate W1 from the nozzle 551a. The catalyst solution N1 supplied onto the substrate W1 is diffused on the surface of the substrate W1 by a centrifugal force which is generated as the substrate W1 is rotated. As a result, a metal film (e.g., a Pd film) having catalytic activity is formed on a plating target surface (e.g., a copper wiring formed on the surface of the substrate W1). The catalyst solution N1 scattered from the substrate W1 is drained through the drain opening 571b of the cup 57 and the liquid draining mechanism 59b. When starting this catalyst solution supplying process, the controller 3 controls the elevating mechanism 58 to adjust the position of the cup 57 such that the drain opening 571b of the cup 57 is located at a position where it faces the peripheral edge portion of the substrate W1.

In the second rinse process, the substrate W1 on which the catalyst layer is formed is rinsed. While rotating the substrate W1 held by the substrate holding unit 52 at a preset speed by controlling the driving unit 524, the controller 3 controls the rinse liquid supply unit 55c to locate the nozzle 551c at a position above the substrate W1, and the rinse liquid N3 is supplied onto the substrate W1 from the nozzle 551c. The rinse liquid N3 supplied onto the substrate W1 is diffused on the surface of the substrate W1 by a centrifugal force which is generated as the substrate W1 is rotated. As a result, the catalyst solution N1 remaining on the substrate W1 is washed away. The rinse liquid N3 scattered from the substrate W1 is drained through the drain opening 571c of the cup 57 and the liquid draining mechanism 59c. When starting this second rinse process, the controller 3 controls the elevating mechanism 58 to adjust the position of the cup 57 such that the drain opening 571c of the cup 57 is located at the position where it faces the peripheral edge portion of the substrate W1

After the above-described pretreatment process is performed, if necessary, the plating process is performed. In the plating process, while rotating the substrate W1 held by the substrate holding unit 52 at a low speed (a speed at which the plating liquid M1 supplied onto the substrate W1 is not scattered from the substrate W1) by controlling the driving unit 524 or while maintaining the substrate W1 held by the substrate holding unit 52 not to be rotated, the controller 3 controls the plating liquid supply unit 53 to locate the nozzle 531 at a position above the substrate W1, and the plating liquid M1 is supplied onto the substrate W1 from the nozzle 531. After a preset amount of the plating liquid M1 is once supplied onto the substrate W1 from the nozzle 531, the controller 3 controls the plating liquid supply unit 53 not to supply new plating liquid M1 until the plating with the supplied plating liquid M1 is finished.

The temperature of the plating liquid M1 supplied from the plating liquid supply unit 53 is lower than the preset plating temperature. Thus, at a time point when the plating liquid M1 is supplied onto the substrate W1 held by the substrate holding unit 52 from the plating liquid supply unit 53, the plating liquid M1 does not exert the preset plating performance, and the plating reaction is not begun, or, even if begun, it progresses very slowly.

After the plating liquid M1 is supplied onto the substrate W1 held by the substrate holding unit 52, the controller 3 controls the elevating mechanism 62 to move the top plate 61 horizontally up to the position where the top plate 61 covers the substantially entire surface region of the substrate W1 and, then, to move the top plate 61 down, so that the top plate 61 is located close to the substrate W1. Accordingly, when the plating liquid M1 supplied onto the substrate W1 is heated by the plating liquid heating unit 63, there is formed the space S between the substrate W1 held by the substrate holding unit 52 and the top plate 61. The space S is surrounded by the cup 57. The space S is not sealed by the cup 57 and communicates with the external space. After the top plate 61 is placed close to the substrate W1, the controller 3 controls the plating liquid heating unit 63 to heat the plating liquid M1 on the substrate W1 to the preset plating temperature. The controller 3 may control the plating liquid heating unit 63 to heat the substrate W1 before the plating liquid M1 is supplied. In such a case, the controller 3 controls the elevating mechanism 62 to move the top plate 61 horizontally up to the position where it covers the substantially entire surface region of the substrate W1 and, then, to move the top plate 61 down, so that the top plate 61 is located near the substrate W1. Then, by controlling the plating liquid heating unit 63, preliminary heating on the substrate W1 is performed.

After the plating liquid M1 is supplied from the plating liquid supply unit 53 onto the substrate W1 held by the substrate holing unit 52, at a time point when the temperature of the plating liquid M1 has reached the preset plating temperature while being heated by the plating liquid heating unit 63, the plating liquid M1 exerts the preset plating performance, so that the plating is begun. During the plating, the controller 3 controls the plating liquid heating unit 63 to allow the temperature of the plating liquid M1 to be maintained at the preset plating temperature. Accordingly, a plating film is formed on the plating target surface of the substrate W1 (on the metal film (e.g., the Pd film), which has catalytic activity and is formed on the surface of the substrate W1, in case that the catalyst solution supplying process is performed).

Through the above processes, the plating on the single sheet of substrate W1 is performed with the plating liquid M1 heated to the preset plating temperature. That is, the controller 3 controls the plating liquid supply unit 53 and the plating liquid heating unit 63 such that, after the preset amount of the plating liquid M1 is supplied to the substrate W1 held by the substrate holding unit 52 one time, the supplied plating liquid M1 is heated to the preset plating temperature by the plating liquid heating unit 63, and the plating is performed with the plating liquid M1 heated to the preset plating temperature.

After the plating liquid M1 is supplied from the plating liquid supply unit 53 onto the substrate W1 held by the substrate holding unit 52, the supplied plating liquid M1 is heated by the plating liquid heating unit 63. As a result, the moisture in the plating liquid M1 is evaporated, and the vapor generated from the plating liquid M1 stays in the space S. The space S is surrounded by the cup 57, but is not sealed by the cup 57 and communicates with the external space (space within the chamber 51). The vapor generated from the plating liquid M1 is flown into the external space after staying in the space S. Accordingly, the moisture in the plating liquid M1 is continuously evaporated. The evaporation amount of the moisture from the plating liquid M1 can be adjusted by controlling the volume of the space S (for example, the distance between the top plate 61 and the substrate W1 held by the substrate holding unit 52). For instance, by reducing the volume of the space S, the evaporation amount of the moisture from the plating liquid M1 can be reduced, and, thus, the sharp increase of the concentration of the plating liquid M1 caused by the evaporation of the moisture can be suppressed. The distance between the top plate 61 and the substrate W1 held by the substrate holding unit 52 may be appropriately controlled based on the set temperature of the top plate, the temperature of the plating liquid after being heated, the temperature rising rate of the plating liquid, the amount of the plating liquid on the substrate, and so forth.

As the plating liquid M1 is heated by the plating liquid heating unit 63 after being supplied from the plating liquid supply unit 53 onto the substrate W1 held by the substrate holding unit 52, the temperature of the plating liquid M1 is increased, and the moisture in the plating liquid M1 is evaporated, so that the concentration of the plating liquid M1 is increased. As a result, the concentration of the plating liquid M1 at a time when the temperature of the plating liquid M1 has reached the preset plating temperature becomes equal to or higher than the lower limit (i.e., CL(%)) of the preset concentration range or equal to or lower than the median value (i.e., (CL+CH)/2) of the preset concentration range.

The plating component of the plating liquid M1 is consumed after the temperature of the plating liquid M1 reaches the preset plating temperature. Since, however, the heating by the plating liquid heating unit 63 is continued, the concentration of the plating liquid M1 is increased. That is, since the increase of the concentration of the plating liquid M1 caused by the evaporation of the moisture from the plating liquid M1 is more dominant than the decrease of the concentration of the plating liquid M1 caused by the consumption of the plating component within the plating liquid M1, the concentration of the plating liquid M1 is increased even after the plating liquid M1 reaches the preset plating temperature, and reaches the upper limit (i.e., CH (%)) of the preset concentration range, shortly.

As the concentration of the plating liquid M1 at the time when the temperature of the plating liquid M1 has reached the preset plating temperature is closer to the lower limit (i.e., CL (%)) of the preset concentration range, a time period taken until the concentration of the plating liquid M1 reaches the upper limit (i.e., CH (%)) of the preset concentration range, that is, a time period during which the plating liquid M1 is used for the plating is lengthened.

The controller 3 finishes the plating by draining the plating liquid M1 from the substrate W1 before the concentration of the plating liquid M1 reaches the upper limit (i.e., CH (%)) of the preset concentration range. When finishing the plating, the controller 3 controls the elevating mechanism 62 to move the top plate 61 up to a preset position and to move the top plate 61 horizontally up to the position where the top plate 61 does not cover the substantially entire surface region of the substrate W1. Thereafter, while rotating the substrate W1 held by the substrate holding unit 52 at a preset speed by controlling the driving unit 524, the controller 3 controls the rinse liquid supply unit 55c to locate the nozzle 551c at a position above the substrate W1, and the rinse liquid N3 is supplied onto the substrate W1 from the nozzle 551c. The plating liquid M1 and the rinse liquid N3 on the substrate W1 are scattered from the substrate W1 by a centrifugal force which is generated as the substrate W1 is rotated, and the plating liquid M1 and the rinse liquid N3 scattered from the substrate W1 are drained through the drain opening 571a of the cup 57 and the liquid draining mechanism 59a. When finishing the plating, the controller 3 controls the elevating mechanism 58 to adjust the position of the cup 57 such that the drain opening 571a of the cup 57 is located at the position where it faces the peripheral edge portion of the substrate W1.

In the plating device 5, it is desirable to perform a drying process of drying the substrate W1 after the plating process. In the drying process, the substrate W1 can be dried naturally by rotating the substrate W1, or by discharging a drying solvent or a drying gas to the substrate W1.

After the plating process, a substrate carry-out process is performed. In the substrate carry-out process, the substrate W2 on which the plating is completed is carried out from the plating device 5. At this time, the controller 3 controls the transfer device 222 to take out the substrate W2 from the plating device 5 and place the taken substrate W2 in the delivery unit 214. Then, the controller 3 controls the transfer device 213 to take out the substrate W2 from the delivery unit 214 and accommodate the substrate W2 in the carrier C in the placing section 211.

From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting.

Claims

1. A plating apparatus having a plating device configured to perform a plating on a substrate at a preset plating temperature; and a controller configured to control an operation of the plating device,

wherein the plating device comprises:
a plating liquid supply unit configured to supply, to the substrate, a plating liquid which allowed to exert a preset plating performance within a preset concentration range; and
a plating liquid heating unit configured to heat the plating liquid supplied to the substrate to the preset plating temperature,
wherein the plating liquid supplied to the substrate from the plating liquid supply unit has an initial temperature adjusted to be lower than the preset plating temperature, and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature while being heated by the plating liquid heating unit is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range, and
the controller controls the plating liquid supply unit and the plating liquid heating unit to perform, by supplying a preset amount of the plating liquid to the substrate a single time and heating the supplied plating liquid to the preset plating temperature, the plating with the plating liquid heated to the preset plating temperature.

2. The plating apparatus of claim 1,

wherein the initial concentration is adjusted such that the concentration of the plating liquid at the moment when the temperature of the plating liquid has reached the preset plating temperature is close to the lower limit of the preset concentration range.

3. The plating apparatus of claim 1,

wherein the initial concentration is adjusted to be lower than the lower limit of the preset concentration range.

4. The plating apparatus of claim 1,

wherein the plating device is equipped with a top plate disposed above the substrate, and
when the plating liquid supplied to the substrate is heated by the plating liquid heating unit, a space in which vapor generated from the plating liquid supplied to the substrate stays is formed between the substrate and the top plate.

5. A plating method of performing a plating on a substrate at a preset plating temperature, the plating method comprising:

a plating liquid supplying process of supplying, to the substrate, a plating liquid which exerts a preset plating performance within a preset concentration range and which has an initial temperature adjusted to be lower than the preset plating temperature; and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range; and
a plating liquid heating process of heating the plating liquid supplied to the substrate to the preset plating temperature,
wherein a preset amount of the plating liquid is supplied to the substrate a single time in the plating liquid supplying process, and
in the plating liquid heating process, the plating liquid supplied in the plating liquid supplying process is heated to the preset plating temperature, and the plating is performed with the plating liquid heated to the preset plating temperature.

6. The plating method of claim 5,

wherein the initial concentration is adjusted such that the concentration of the plating liquid at the moment when the temperature of the plating liquid has reached the preset plating temperature is close to the lower limit of the preset concentration range.

7. The plating method of claim 5,

wherein the initial concentration is adjusted to be lower than the lower limit of the preset concentration range.

8. The plating method of claim 5,

wherein the plating liquid heating process is performed in a state where a space in which vapor generated from the plating liquid supplied to the substrate stays is formed between the substrate and a top plate disposed above the substrate.

9. A computer-readable recording medium having stored thereon computer-executable instructions that, in response to execution, cause a plating apparatus to perform a plating method as claimed in claim 5.

Patent History
Publication number: 20170121822
Type: Application
Filed: Oct 25, 2016
Publication Date: May 4, 2017
Inventors: Nobutaka Mizutani (Nirasaki City), Mitsuaki Iwashita (Nirasaki City), Yuichiro Inatomi (Nirasaki City)
Application Number: 15/333,303
Classifications
International Classification: C23C 18/16 (20060101); C23C 18/52 (20060101); C23C 18/31 (20060101);