Methods and apparatus for electrically and/or chemically-mechanically removing conductive material from a microelectronic substrate
A method and apparatus for removing conductive material from a microelectronic substrate. In one embodiment, a support member supports a microelectronic substrate relative to a material removal medium, which can include first and second electrodes and a polishing pad. One or more electrolytes are disposed between the electrodes and the microelectronic substrate to electrically link the electrodes to the microelectronic substrate. The electrodes are then coupled to a source of varying current that electrically removes the conductive material from the substrate. The microelectronic substrate and/or the electrodes can be moved relative to each other to position the electrodes relative to a selected portion of the microelectronic substrate, and/or to polish the microelectronic substrate. The material removal medium can remove gas formed during the process from the microelectronic substrate and/or the electrodes. The medium can also have different first and second electrical characteristics to provide different levels of electrical coupling to different regions of the microelectronic substrate.
The present application is a continuation-in-part of U.S. application Ser. No. 09/651,779 (attorney docket number 108298515US), titled “Methods and Apparatus for Removing Conductive Material From a Microelectronic Substrate,” filed Aug. 30, 2000, and U.S. application No. ______ (attorney docket number 108298515US1), titled “Methods and Apparatus for Electrical, Mechanical and/or Chemical Removal of Conductive Material From a Microelectronic Substrate,” filed concurrently herewith, and U.S. application No. ______ (attorney docket number 108298515US2), titled “Microelectronic Substrate Having Conductive Material With Blunt Cornered Apertures, and Associated Methods for Removing Conductive Material,” filed concurrently herewith, all incorporated herein in their entireties by reference.
TECHNICAL FIELDThis invention relates to methods and apparatuses for removing conductive material from microelectronic substrates.
BACKGROUNDMicroelectronic substrates and substrate assemblies typically include a semiconductor material having features, such as memory cells, that are linked with conductive lines. The conductive lines can be formed by first forming trenches or other recesses in the semiconductor material, and then overlaying a conductive material (such as a metal) in the trenches. The conductive material is then selectively removed to leave conductive lines extending from one feature in the semiconductor material to another.
Electrolytic techniques have been used to both deposit and remove metallic layers from semiconductor substrates. For example, an alternating current can be applied to a conductive layer via an intermediate electrolyte to remove portions of the layer. In one arrangement, shown in
One drawback with the arrangement shown in
One approach to addressing some of the foregoing drawbacks is to attach a plurality of first electrodes 20a around the periphery of the substrate 10 to increase the uniformity with which the conductive material is removed. However, islands of conductive material may still remain despite the additional first electrodes 20a. Another approach is to form the electrodes 20a and 20b from an inert material, such as carbon, and remove the barrier 22 to increase the area of the conductive layer 11 in contact with the electrolyte 31. However, such inert electrodes may not be as effective as more reactive electrodes at removing the conductive material, and the inert electrodes may still leave residual conductive material on the substrate 10.
International Application PCT/US00/08336 (published as WO/00/59682) discloses an apparatus having a first chamber for applying a conductive material to a semiconductor wafer, and a second chamber for removing conductive material from the semiconductor wafer by electropolishing or chemical-mechanical polishing. The second chamber includes an anode having a paint roller configuration with a cylindrical mechanical pad that contacts both an electrolyte bath and the face of the wafer as the anode and the wafer rotate about perpendicular axes. A cathode, which can include a conductive liquid isolated from the electrolytic bath, is electrically coupled to an edge of the wafer. One drawback with this device is that it, too, can leave islands of residual conductive material on the wafer.
Another drawback with some conventional devices is that they may not adequately control gas bubbles that evolve during the electrolytic process. These bubbles can collect on the electrode and/or the microelectronic substrate and can interfere with the uniform removal of material from the substrate. Still further, conventional electrolytic processes may not provide adequate control over the rate at which material is removed from the substrate, or the location on the substrate from which the material is removed.
SUMMARYThe present invention is directed toward methods in apparatuses for removing conductive materials from microelectronic substrates. A method in accordance with one embodiment of the invention includes spacing first and second conductive electrodes apart from the microelectronic substrate. The method can further include disposing an electrolyte between the microelectronic substrate and both the first and second electrodes, with both the first and second electrodes in fluid communication with the electrolyte. At least part of the conductive material is removed from the microelectronic substrate by passing a varying current through at least one of the first and second electrodes while the electrodes are spaced apart from the conductive material of the substrate. The method can further include removing gas from a region between the microelectronic substrate and at least one of the electrodes while the conductive material is removed from the microelectronic substrate. In a further aspect of the invention, the microelectronic substrate can be engaged with a polishing surface of a polishing pad and at least one of the microelectronic substrate and the polishing pad can be moved relative to the other while the varying current is passed through the conductive material.
A method in accordance with another aspect of the invention includes aligning a first portion of the microelectronic substrate with a first portion of a material removal medium having first electrical characteristics. The method can further include aligning a second portion of the microelectronic substrate with a second portion of the material removal medium having second electrical characteristics different than the first electrical characteristics. The conductive material can be engaged with a polishing surface of the material removal medium and at least a portion of the electrically conductive material can be removed from the microelectronic substrate by passing a varying electrical current through the conductive material while engaging the conductive material with the material removal medium and moving at least one of the substrate and medium relative to the other.
The invention is also directed toward an apparatus for removing conductive material from a microelectronic substrate. In one aspect of the invention, the apparatus can include a support member having at least one engaging surface to support a microelectronic substrate. A material removal medium is positioned proximate to the support member. The material removal medium can include a first electrode and a second electrode positioned to be spaced apart from the microelectronic substrate when the microelectronic substrate is supported by the support member. At least one of the first and second electrodes is coupleable to a source of varying electrical current. The material removal medium can further include a gas removal surface positioned to remove gas from a region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.
In another aspect of the invention, the material removal medium can include a polishing surface positioned to engage the microelectronic substrate when the substrate is supported by the support member. At least one of the medium and the support member can be movable relative to the other and the medium can include a first region with a first electrical characteristic and a second region with a second electrical characteristic different than the first electrical characteristic. The first region can be aligned with a first portion of the microelectronic substrate and the second region can be aligned with a second portion of the microelectronic substrate when the polishing surface is engaged with the microelectronic substrate. First and second electrodes are positioned proximate to the polishing surface with at least one of the electrodes being coupleable to a source of varying electrical current.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 12A-B schematically illustrate a circuit and waveform for electrolytically processing a microelectronic substrate in accordance with yet another embodiment of the invention.
The present disclosure describes methods and apparatuses for removing conductive materials from a microelectronic substrate and/or substrate assembly used in the fabrication of microelectronic devices. Many specific details of certain embodiments of the invention are set forth in the following description and in
The microelectronic substrate 110 has an edge surface 112 and two face surfaces 113. A support member 140 supports the microelectronic substrate 110 relative to the vessel 130 so that a conductive layer 111 on at least one of the face surfaces 113 of the substrate 110 contacts the electrolyte 131. The conductive layer 111 can include metals such as platinum, tungsten, tantalum, gold, copper, or other conductive materials. In another aspect of this embodiment, the support member 140 is coupled to a substrate drive unit 141 that moves the support member 140 and the substrate 110 relative to the vessel 130. For example, the substrate drive unit 141 can translate the support member 140 (as indicated by arrow “A”) and/or rotate the support member 140 (as indicated by arrow “B”).
The apparatus 160 can further include a first electrode 120a and a second electrode 120b (referred to collectively as electrodes 120) supported relative to the microelectronic substrate 110 by a support member 124. In one aspect of this embodiment, the support arm 124 is coupled to an electrode drive unit 123 for moving the electrodes 120 relative to the microelectronic substrate 110. For example, the electrode drive unit 123 can move the electrodes toward and away from the conductive layer 111 of the microelectronic substrate 110, (as indicated by arrow “C”), and/or transversely (as indicated by arrow “D”) in a plane generally parallel to the conductive layer 111. Alternatively, the electrode drive unit 123 can move the electrodes in other fashions, or the electrode drive unit 123 can be eliminated when the substrate drive unit 141 provides sufficient relative motion between the substrate 110 and the electrodes 120.
In either embodiment described above with reference to
In one aspect of an embodiment of the apparatus 160 shown in
One feature of an embodiment of the apparatus 160 shown in
Another feature of an embodiment of the apparatus 160 described above with reference to
In one aspect of the embodiment shown in
In another aspect of the embodiment shown in
The sensor 251 and the sensor control unit 252 can have any of a number of suitable configurations. For example, in one embodiment, the sensor 251 can be an optical sensor that detects removal of the conductive layer 111 by detecting a change in the intensity, wavelength or phase shift of the light reflected from the substrate 110 when the conductive material is removed. Alternatively, the sensor 251 can emit and detect reflections of radiation having other wavelengths, for example, x-ray radiation. In still another embodiment, the sensor 251 can measure a change in resistance or capacitance of the conductive layer 111 between two selected points. In a further aspect of this embodiment, one or both of the electrodes 220 can perform the function of the sensor 251 (as well as the material removal function described above), eliminating the need for a separate sensor 251. In still further embodiments, the sensor 251 can detect a change in the voltage and/or current drawn from the current supply 221 as the conductive layer 111 is removed.
In any of the embodiments described above with reference to
Another feature of an embodiment of the apparatus 260 described above with reference to
In one aspect of this embodiment, the first electrolyte vessels 330a include a flow restrictor 322, such as a permeable isolation membrane formed from Teflon™, sintered materials such as sintered glass, quartz or sapphire, or other suitable porous materials that allow ions to pass back and forth between the first electrolyte vessels 330a and the second electrolyte vessel 330b, but do not allow the second electrolyte 330b to pass inwardly toward the electrodes 320 (for example, in a manner generally similar to a salt bridge). Alternatively, the first electrolyte 331a can be supplied to the electrode vessels 330a from a first electrolyte source 339 at a pressure and rate sufficient to direct the first electrolyte 331a outwardly through the flow restrictor 322 without allowing the first electrolyte 331a or the second electrolyte 330b to return through the flow restrictor 322. In either embodiment, the second electrolyte 331b remains electrically coupled to the electrodes 320 by the flow of the first electrolyte 331a through the restrictor 322.
In one aspect of this embodiment, the apparatus 360 can also include a support member 340 that supports the substrate 110 with the conductive layer 111 facing toward the electrodes 320. For example, the support member 340 can be positioned in the second electrolyte vessel 330b. In a further aspect of this embodiment, the support member 340 and/or the electrodes 320 can be movable relative to each other by one or more drive units (not shown).
One feature of an embodiment of the apparatus 360 described above with reference to
In one embodiment, electrodes 720a and 720b can be grouped to form an electrode pair 770a, with each electrode 720a and 720b coupled to an opposite terminal of a current supply 121 (
In an alternate embodiment, electrodes 720c and 720d can be grouped to form an electrode pair 770b, and each electrode 720c and 720d can have a wedge or “pie” shape that tapers inwardly toward the center of the microelectronic substrate 110. In still another embodiment, narrow, strip-type electrodes 720e and 720f can be grouped to form electrode pairs 770c, with each electrode 720e and 720f extending radially outwardly from the center 113 of the microelectronic substrate 110 toward the periphery 112 of the microelectronic substrate 110.
In still another embodiment, a single electrode 720g can extend over approximately half the area of the microelectronic substrate 110 and can have a semicircular planform shape. The electrode 720g can be grouped with another electrode (not shown) having a shape corresponding to a mirror image of the electrode 720g, and both electrodes can be coupled to the current source 121 to provide alternating current to the microelectronic substrate in any of the manners described above with reference to
In other embodiments, the electrode 720c can have other shapes. For example, the lower surface 772 can have a curved rather than a flat profile. Alternatively, any of the electrodes described above with reference to
In one aspect of this embodiment, the first lead 428a can be offset from the second lead 428b to reduce the likelihood for short circuits and/or capacitive coupling between the leads. In a further aspect of this embodiment, the electrode support 473 can have a configuration generally similar to any of those described above with reference to
In still a further aspect of this embodiment, the electrode pairs 470 shown in
In another embodiment, shown in
One feature of the electrodes 820 described above with respect to
The apparatus 560 can also have a plurality of rollers to guide, position and hold the polishing pad 582 over the top-panel 581. The rollers can include a supply roller 583, first and second idler rollers 584a and 584b, first and second guide rollers 585a and 585b, and a take-up roller 586. The supply roller 583 carries an unused or pre-operative portion of the polishing pad 582, and the take-up roller 583 carries a used or post-operative portion of the polishing pad 582. Additionally, the first idler roller 584a and the first guide roller 585a can stretch the polishing pad 582 over the top-panel 581 to hold the polishing pad 582 stationary during operation. A motor (not shown) drives at least one of the supply roller 583 and the take-up roller 586 to sequentially advance the polishing pad 582 across the top-panel 581. Accordingly, clean pre-operative sections of the polishing pad 582 may be quickly substituted for used sections to provide a consistent surface for polishing and/or cleaning the substrate 110.
The apparatus 560 can also have a carrier assembly 590 that controls and protects the substrate 110 during the material removal processes. The carrier assembly 590 can include a substrate holder 592 to pick up, hold and release the substrate 110 at appropriate stages of the material removal process. The carrier assembly 590 can also have a support gantry 594 carrying a drive assembly 595 that can translate along the gantry 594. The drive assembly 595 can have an actuator 596, a drive shaft 597 coupled to the actuator 596, and an arm 598 projecting from the drive shaft 597. The arm 598 carries the substrate holder 592 via a terminal shaft 599 such that the drive assembly 595 orbits the substrate holder 592 about an axis E-E (as indicated by arrow “R1”). The terminal shaft 599 may also rotate the substrate holder 592 about its central axis F-F (as indicated by arrow “R2”).
In one embodiment, the polishing pad 582 and a planarizing solution 587 define at least a portion of a material removal medium that mechanically and/or chemically-mechanically removes material from the surface of the substrate 110. The polishing pad 582 used in the apparatus 560 can be a fixed-abrasive polishing pad having abrasive particles that are fixedly bonded to a suspension medium. Accordingly, the planarizing solution 587 can be a “clean solution” without abrasive particles because the abrasive particles are fixedly distributed across a polishing surface 588 of the polishing pad 582. In other applications, the polishing pad 582 may be a non-abrasive pad without abrasive particles, and the planarizing solution 587 can be a slurry with abrasive particles and chemicals to remove material from the substrate 110.
To remove material from the substrate 110 with the apparatus 560, the carrier assembly 590 presses the face 113 of the substrate 110 against the polishing surface 588 of the polishing pad 582 in the presence of the planarizing solution 587. The drive assembly 595 then orbits the substrate holder 592 about the axis E-E and optionally rotates the substrate holder 592 about the axis F-F to translate the substrate 110 across the planarizing surface 588. As a result, the abrasive particles and/or the chemicals in the material removal medium remove material from the surface of the substrate 110 in a chemical and/or chemical-mechanical planarization (CMP) process. Accordingly, in one embodiment, the polishing pad 582 can smooth the substrate 110 by removing rough features projecting from the conductive layer 111 of the substrate 110.
In a further aspect of this embodiment, the apparatus 560 can include an electrolyte supply vessel 530 that delivers an electrolyte to the planarizing surface 588 of the polishing pad 582 with a conduit 537, as described in greater detail with reference to
In one aspect of an embodiment of the apparatus 560 described above with reference to
Another advantage of an embodiment of the apparatus 560 described above with reference to
The electrodes 520a and 520b can be electrically coupled to the microelectronic substrate 110 (
In either embodiment, the electrodes 520a and 520b can be in fluid communication with each other and the conductive layer 111 via a common volume of electrolyte 531. Each electrode 520a, 520b can be more directly electrically coupled to the conductive layer 111 (
In one aspect of an embodiment of the apparatus shown in
In any of the embodiments described above with reference to
The carrier assembly 690 controls and protects the microelectronic substrate 110 during the material removal process. The carrier assembly 690 typically has a substrate holder 692 with a pad 694 that holds the microelectronic substrate 110 via suction. A drive assembly 696 of the carrier assembly 690 typically rotates and/or translates the substrate holder 692 (arrows “I” and “J,” respectively). Alternatively, the substrate holder 692 may include a weighted, free-floating disk (not shown) that slides over the polishing pad 682.
To planarize the microelectronic substrate 110 with the apparatus 660 in one embodiment, the carrier assembly 690 presses the microelectronic substrate 110 against a polishing surface 688 of the polishing pad 682. The platen 680 and/or the substrate holder 692 then move relative to one another to translate the microelectronic substrate 110 across the polishing surface 688. As a result, the abrasive particles in the polishing pad 682 and/or the chemicals in the planarizing liquid 687 remove material from the surface of the microelectronic substrate 110.
The apparatus 660 can also include a current source 621 coupled with leads 628a and 628b to one or more electrode pairs 670 (one of which is shown in
In one aspect of an embodiment shown in
An advantage of this arrangement is that the high frequency signal can transmit the required electrical energy from the electrodes 520a and 520b to the microelectronic substrate 110, while the low frequency superimposed signal can more effectively promote the electrochemical reaction between the electrolyte 531 and the conductive layer 111 of the microelectronic substrate 110. Accordingly, any of the embodiments described above with reference to
The apparatus 960 can further include a material removal medium 930 that removes at least part of the conductive material 111 from the substrate 110. In one aspect of this embodiment, the material removal medium 930 can include first and second electrodes 920a, 920b supported by an electrode support 937 and coupled to an electrical potential source 921, such as an alternating current source or a pulsed direct current source. The material removal medium 930 can further include a polishing pad 982 having a first portion 982a adjacent to the first electrode 920a and a second portion 982b adjacent to the second electrode 920b. The material removal medium 930 can move relative to the support member 940 (and the microelectronic substrate 110) as indicated by arrows “H” and “G.”
A fluid 931 can be disposed between the microelectronic substrate 110 and a polishing surface 988 of the polishing pad 982 to facilitate electrical and/or chemical-mechanical removal of the conductive material 111. For example, the fluid 931 can include an electrolyte that electrically couples the first and second electrodes 920a, 920b to the conductive material 111 on at least a substantial portion of the face surface 113, as was generally described above. The fluid 931 can also include chemicals and/or abrasive elements to chemically and/or mechanically remove at least some of the conductive material 111 from the substrate 110. Alternatively, the polishing pad 982 (rather than the fluid 931) can include abrasive elements. Accordingly, the combination of electrical and chemical-mechanical removal techniques in one embodiment of the apparatus 960 can provide the user with an increased level of control over the rate at which the conductive material 111 is removed from the substrate 110, the amount of conductive material 111 removed, and/or the region of the microelectronic substrate 110 from which the conductive material 111 is removed.
In a further aspect of this embodiment, the electrodes 920c, 920d can be separated from each other by a gap 928. The gap can reduce or eliminate direct electrical coupling between the two electrodes, so that the current instead flows from one electrode through the conductive material 111 of the microelectronic substrate 110 to the other electrode. Furthermore, the gap 928 can operate in addition to, or in lieu of the channels 925 to conduct gas bubbles away from the electrodes 920c, 920d and/or the microelectronic substrate 110. In still a further aspect of this embodiment, the electrode support 937 can rotate (as indicated by arrow “G”) at a rate sufficient to move the gas bubbles radially outwardly by centrifugal force.
Another feature of the apparatus 960a shown in
In another aspect of an embodiment of the apparatus 1060 shown in
One feature of an embodiment of the apparatus described above with reference to
In one aspect of this embodiment, the apparatus 1160 can further include pairs of first and second electrodes 1120a, 1120b positioned beneath, and/or integrated with the polishing pad 1182. Each electrode 1120a, 1120b can have a surface 1127 facing toward the microelectronic substrate 110 and can be adjacent to a divider 1128 that electrically isolates the first electrode 1120a from the second electrode 1120b. The apparatus 1160 can further include a conduit 1138 that provides the processing fluid 1131 to the polishing pad 1182 where it can travel upwardly through pores or passages (not shown in
In a further aspect of this embodiment, the apparatus 1160 can include an ultrasonic energy emitter 1112 in fluid communication with the material removal fluid 1131. The ultrasonic energy emitter 1112 can transmit ultrasonic energy into the fluid 1131, which can increase the rate and/or efficiency with which gas bubbles are removed from the region proximate to the microelectronic substrate 110.
In one aspect of this embodiment, a first electrolytic fluid supplied to the first supply conduit 1338a can be different than a second electrolytic fluid supplied to the second conduit 1338b, and both the first and second electrolytic fluids can be different than a third electrolytic fluid supplied to the third supply conduit 1338c. For example, the first, second, and third electrolytic fluids can have different chemical compositions and/or different concentrations of the same chemical agent or agents. In either embodiment, the impedance of an electrical circuit that includes the first region 1382a and the conductive material 111 can be different than the impedance of an electrical circuit that includes the second region 1382b and the conductive material 111. Accordingly, the degree to which the electrodes 1320a, 1320b are electrically coupled to the microelectronic substrate 110 can vary over the face of the microelectronic substrate 110, providing control over the rate at which material are electrically removed from the microelectronic substrate.
From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. For example, some or all of the techniques described above in the context of a web-format apparatus (such as the one shown in
Claims
1-64. (Canceled)
65. An apparatus for removing conductive material from a microelectronic substrate, comprising:
- a support member configured to support a microelectronic substrate; and
- a material removal medium proximate to the support member, the material removal medium including a first electrode and a second electrode positioned to be spaced apart from the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current, the material removal medium further including a gas removal surface positioned to remove gas from a region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.
66. The apparatus of claim 65 wherein the microelectronic substrate has a face surface and an edge surface, and wherein the material removal medium includes a polishing surface disposed between the face surface and both the first and second electrodes during operation.
67. The apparatus of claim 65, further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurized fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurized fluid during operation.
68. The apparatus of claim 65, further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurizing fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurizing fluid during operation, at least a portion of the first surface of the polishing pad being spaced apart from the first electrode to define a fluid passage, the fluid passage having an entrance coupleable to a source of electrolytic fluid, the fluid passage further having an exit.
69. The apparatus of claim 68, further comprising a vacuum source coupled to the exit of the fluid passage.
70. The apparatus of claim 65 wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate when the support member supports the microelectronic substrate.
71. The apparatus of claim 65 wherein the substrate support member is positioned to support the microelectronic substrate from below and the material removal medium is positioned above the substrate support.
72. The apparatus of claim 65 wherein at least one of the substrate support member and the material removal medium is rotatable at a rate sufficient to direct the gas radially outwardly and away from the microelectronic substrate.
73. The apparatus of claim 65, further comprising the microelectronic substrate.
74. The apparatus of claim 65, further comprising a liquid electrolyte disposed adjacent to the material removal medium.
75. The apparatus of claim 65 wherein the gas removal surface is one of a plurality of gas removal surfaces positioned to define a gas removal channel.
76. The apparatus of claim 65 wherein the material removal medium includes a medium support member supporting the first and second electrodes, and wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein the planarizing medium further includes a polishing pad positioned adjacent to at least one of the first and second electrodes and having the polishing surface facing downwardly and engaged with the microelectronic substrate during operation, the first and second electrodes being spaced apart from each other with the gas removal surface positioned above the microelectronic substrate during operation to collect the gas from the region proximate to the microelectronic substrate.
77. The apparatus of claim 65 wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein the gas removal surface is recessed into at least one of the downwardly facing surfaces.
78. The apparatus of claim 65 wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein at least one of the downwardly facing surfaces is non-horizontal to conduct gas away from the region proximate to the microelectronic substrate.
79. The apparatus of claim 65 wherein the material removal medium includes a porous polishing pad having a polishing surface with pores facing toward the microelectronic substrate during operation, and wherein the gas removal surface is in fluid communication with at least one of the pores to conduct gas away from the region.
80. An apparatus for removing conductive material from a microelectronic substrate, comprising:
- a support member configured to support a microelectronic substrate;
- a material removal medium proximate to the support member, the material removal medium including a first electrode and a second electrode each positioned to be spaced apart from the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current; and
- an ultrasonic energy emitter positioned proximate to the material removal medium to remove gas from a region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.
81. The apparatus of claim 80 wherein the ultrasonic energy emitter is positioned to contact an electrolytic fluid when the electrolytic fluid is disposed between the microelectronic substrate and at least one of the first and second electrodes.
82. The apparatus of claim 80 wherein the material removal medium further includes a gas removal surface positioned to remove the gas from the region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.
83. The apparatus of claim 80 wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate when the support member supports the microelectronic substrate.
84. An apparatus for removing conductive material from a microelectronic substrate, comprising:
- a substrate support member configured to support a microelectronic substrate;
- a material removal medium proximate to the substrate support member and having a polishing surface positioned to engage the microelectronic substrate when the microelectronic substrate is supported by the substrate support member, at least one of the material removal medium and the substrate support member being movable relative to the other, the material removal medium further having a first electrode at least proximate to the polishing surface and a second electrode at least proximate to the polishing surface and spaced apart from the first electrode, at least one of the first and second electrodes being coupleable to a source of varying electrical current, at least one of the substrate support member and the planarizing medium having a gas removal surface positioned to receive and remove gas from a region proximate to the microelectronic substrate during operation.
85. The apparatus of claim 84 wherein the microelectronic substrate has a face surface and an edge surface, and wherein the material removal medium includes a polishing surface disposed between the face surface and both the first and second electrodes during operation.
86. The apparatus of claim 84, further comprising the source of varying electrical current, and wherein the source coupled to at least one of the electrodes to transmit to the at least one electrode alternating current and/or pulsed direct current.
87. The apparatus of claim 84 wherein the substrate support is positioned to support the microelectronic substrate from below and the polishing surface is positioned to engage an upward facing surface of the microelectronic substrate.
88. The apparatus of claim 84, further comprising the microelectronic substrate.
89. The apparatus of claim 84 wherein the polishing surface has pores facing toward the microelectronic substrate during operation, and wherein the gas removal surface is in fluid communication with at least one of the pores to conduct gas away from the region proximate to the microelectronic substrate.
90. The apparatus of claim 84, further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurizing fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurizing fluid during operation, at least a portion of the first surface of the polishing pad being spaced apart from the first electrode to define a fluid passage, the fluid passage having an entrance coupleable to a source of electrolytic fluid and an exit, the fluid passage being positioned to entrain gas from at least one of first electrode and the first surface of the polishing pad.
91. An apparatus for removing conductive material from a face surface of a microelectronic substrate, comprising:
- a substrate support member configured to support a microelectronic substrate; and
- a material removal medium positioned proximate to the substrate support member, the material removal medium having a medium support member and first and second electrodes supported by the medium support member, both the first and second electrodes facing toward the face surface of the microelectronic substrate during operation, the material removal medium further including a polishing pad at least proximate to the first and second electrodes and engaged with the microelectronic substrate when the substrate support member support the microelectronic substrate.
92. The apparatus of claim 91 wherein the polishing pad is interposed between at least a portion of the electrode surfaces and the microelectronic substrate during operation.
93. The apparatus of claim 91 wherein the polishing pad depends from at least one of the least electrodes.
94. The apparatus of claim 91 wherein the material removal medium further includes a gas removal surface positioned to receive and remove gas from a region proximate to the microelectronic substrate during operation.
95. The apparatus of claim 91 wherein the material removal medium has first and second regions positioned to be electrically coupled to the microelectronic substrate, the first region having a first electrical characteristic, the second region having a second electrical characteristic different than the first electrical characteristic.
96. An apparatus for removing conductive material from a microelectronic substrate, comprising:
- a support member configured to support a microelectronic substrate; and
- a material removal medium proximate to the support member and having a polishing surface positioned to engage the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the material removal medium and the support member being movable relative to the other, the material removal medium having a first region with a first electrical characteristic and a second region with a second electrical characteristic different than the first electrical characteristic, the first region being aligned with a first portion of the microelectronic substrate and the second region being aligned with a second portion of the microelectronic substrate when the polishing surface is engaged with the microelectronic substrate, the material removal medium further including a first electrode proximate to the polishing surface and a second electrode proximate to the polishing surface, at least one of the first and second electrodes being coupleable to a source of varying electrical current.
97. The apparatus of claim 96 wherein the material removal medium includes a polishing pad having the polishing surface, further wherein the polishing pad has a first dielectric constant in the first region and a second dielectric constant in the second region, the first dielectric constant being different than the second dielectric constant.
98. The apparatus of claim 96 wherein the material removal medium includes a polishing pad having the polishing surface, the polishing pad being generally porous in the first region and generally non-porous in the second region.
99. The apparatus of claim 96 wherein the material removal medium includes a polishing pad having the polishing surface, the polishing pad having a first porosity in the first region and a second porosity different than the first porosity in the second region.
100. The apparatus of claim 96 wherein the material removal medium includes a generally porous polishing pad having the polishing surface, and wherein the material removal medium further includes a generally non-porous blocking material adjacent to the polishing pad in the first region to block pores of the polishing pad in the first region.
101. An apparatus for removing conductive material from a microelectronic substrate, comprising:
- a support member configured to support a microelectronic substrate; and
- a material removal medium proximate to the support member and having a first region with a first electrical characteristic and a second region with a second electrical characteristic different than the first electrical characteristic, the first region being aligned with a first portion of the microelectronic substrate and the second region being aligned with a second portion of the microelectronic substrate when the support member supports the microelectronic substrate, the material removal medium further including a first electrode and a second electrode at least proximate to the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current.
102. The apparatus of claim 101 wherein the material removal medium further includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation.
103. The apparatus of claim 101 wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, further wherein the polishing pad has a first dielectric constant in the first region and a second dielectric constant in the second region, the first dielectric constant being different than the second dielectric constant.
104. The apparatus of claim 101 wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, the polishing pad being generally porous in the first region and generally non-porous in the second region.
105. The apparatus of claim 101 wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, the polishing pad having a first porosity in the first region and a second porosity different than the first porosity in the second region.
106. The apparatus of claim 101 wherein the material removal medium includes a generally porous polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, and wherein the material removal medium further includes a generally non-porous blocking material adjacent to the polishing pad in the first region to block pores of the polishing pad in the first region.
107. The apparatus of claim 101 wherein the material removal medium includes a first electrolytic fluid in the first region and a second electrolytic fluid in the second region, the second electrolytic fluid being different than the first electrolytic fluid.
Type: Application
Filed: Aug 24, 2004
Publication Date: Feb 17, 2005
Inventors: Whonchee Lee (Boise, ID), Scott Meikle (Boise, ID), Scott Moore (Meridian, ID)
Application Number: 10/926,202