Abstract: This p-type silicon wafer was subjected to heat treatment to have a resistivity of 10 ?·cm or more, a BMD density of 5×107 defects/cm3 or more, and an n-type impurity concentration of 1×1014 atoms/cm3 or less at a depth of within 5 ?m from a surface of the wafer. This method for heat-treating p-type silicon wafers, the method includes the steps of: loading p-type silicon wafers onto a wafer boat, inserting into a vertical furnace, and holding in an argon gas ambient atmosphere at a temperature of 1100 to 1300° C. for one hour; moving the wafer boat to a transfer chamber and discharging the silicon wafers; and transferring to the wafer boat silicon wafers to be heat treated next, wherein after the discharge of the heat-treated silicon wafers, the silicon wafers to be heat-treated next are transferred to the wafer boat within a waiting time of less than two hours.

Abstract: A bonded wafer is thinned from an active layer wafer side, and a thinning stop layer is exposed. Thereafter, the layer is made porous in an HF solution, and then the layer is polished and removed. Thus, the removal of the layer is easy; productivity of substrates is high; no defect is caused due to heat treatment; and evenness in polish amount within a wafer surface can be maintained.

Abstract: The present invention provides a method of manufacturing a bonded wafer. The method comprises an oxidation step in which an oxide film is formed on at least one surface of a base wafer, a bonding step in which the base wafer on which the oxide film has been formed is bonded to a top wafer to form a bonded wafer, and a thinning step in which the top wafer included in the bonded wafer is thinned. The oxidation step comprises heating the base wafer to a heating temperature ranging from 800 to 1300° C. at a rate of temperature increase ranging from 1 to 300° C./second in an oxidizing atmosphere, and the bonding step is carried out so as to position the oxide film formed in the oxidation step at an interface of the top wafer and the base wafer.

Abstract: There is provided a layer transferred wafer subjected to a process for regenerating to be reused many times for an SOI layer wafer which is used to manufacture an SOI wafer with an excellent process yield in which oxygen precipitate nuclei or oxygen precipitates are eliminated and generation of HF defects are inhibited by performing the process for regenerating the layer transferred wafer generated as a by-product by an ion implantation separation method. The process for regenerating a layer transferred wafer in which the layer transferred wafer 11b obtained as a by-product in manufacturing a bonded SOI wafer 10 by an ion implantation separation method so as to be reused for an SOI layer wafer 11 of the bonded SOI wafer 10, comprises: rapidly heating the layer transferred wafer 11b in an oxidizing atmosphere, then holding it for a fixed time and subsequently rapidly cooling it; and mirror-polishing a surface of the layer transferred wafer 11b.

Abstract: A bonded wafer is produced by a method comprising a step of implanting ions of a light element such as hydrogen, helium or the like into a wafer for active layer at a predetermined depth position to form an ion implanted layer, a step of bonding the wafer for active layer to a wafer for support substrate through an insulating film, a step of exfoliating the wafer at the ion implanted layer, a first heat treatment step of conducting a sacrificial oxidation for reducing damage on a surface of an active layer exposed through the exfoliation and a second heat treatment step of raising a bonding strength, in which the second heat treatment step is continuously conducted after the first heat treatment step without removing an oxide film formed on the surface of the active layer.

Abstract: A bonded wafer is produced by a step of forming an oxygen ion implanted layer, a step of forming a wafer composite, a step of exposing the oxygen ion implanted layer, and a step of obtaining an active layer, wherein the exposed oxygen ion implanted layer is removed by sequentially subjecting to a first HF treatment, a given oxidation heat treatment, and then a second HF treatment.

Abstract: This p-type silicon wafer was subjected to heat treatment to have a resistivity of 10 ?·cm or more, a BMD density of 5×107 defects/cm3 or more, and an n-type impurity concentration of 1×1014 atoms/cm3 or less at a depth of within 5 ?m from a surface of the wafer. This method for heat-treating p-type silicon wafers, the method includes the steps of: loading p-type silicon wafers onto a wafer boat, inserting into a vertical furnace, and holding in an argon gas ambient atmosphere at a temperature of 1100 to 1300° C. for one hour; moving the wafer boat to a transfer chamber and discharging the silicon wafers; and transferring to the wafer boat silicon wafers to be heat treated next, wherein after the discharge of the heat-treated silicon wafers, the silicon wafers to be heat-treated next are transferred to the wafer boat within a waiting time of less than two hours.

Abstract: In the method for producing a bonded wafer by bonding a wafer for active layer to a wafer for support layer and then thinning the wafer for active layer, when oxygen ions are implanted into the wafer for active layer, the implantation step is divided into two stages conducted under specified conditions.

Abstract: This p-type silicon wafer was subjected to heat treatment to have a resistivity of 10 ?·cm or more, a BMD density of 5×107 defects/cm3 or more, and an n-type impurity concentration of 1×1014 atoms/cm3 or less at a depth of within 5 ?m from a surface of the wafer. This method for heat-treating p-type silicon wafers, the method includes the steps of: loading p-type silicon wafers onto a wafer boat, inserting into a vertical furnace, and holding in an argon gas ambient atmosphere at a temperature of 1100 to 1300° C. for one hour; moving the wafer boat to a transfer chamber and discharging the silicon wafers; and transferring to the wafer boat silicon wafers to be heat treated next, wherein after the discharge of the heat-treated silicon wafers, the silicon wafers to be heat-treated next are transferred to the wafer boat within a waiting time of less than two hours.

Abstract: The present invention provides a method of manufacturing a bonded wafer. The method comprises an oxidation step in which an oxide film is formed on at least one surface of a base wafer, a bonding step in which the base wafer on which the oxide film has been formed is bonded to a top wafer to form a bonded wafer, and a thinning step in which the top wafer included in the bonded wafer is thinned. The oxidation step comprises heating the base wafer to a heating temperature ranging from 800 to 1300° C. at a rate of temperature increase ranging from 1 to 300° C./second in an oxidizing atmosphere, and the bonding step is carried out so as to position the oxide film formed in the oxidation step at an interface of the top wafer and the base wafer.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: There is provided a layer transferred wafer subjected to a process for regenerating to be reused many times for an SOI layer wafer which is used to manufacture an SOI wafer with an excellent process yield in which oxygen precipitate nuclei or oxygen precipitates are eliminated and generation of HF defects are inhibited by performing the process for regenerating the layer transferred wafer generated as a by-product by an ion implantation separation method. The process for regenerating a layer transferred wafer in which the layer transferred wafer 11b obtained as a by-product in manufacturing a bonded SOI wafer 10 by an ion implantation separation method so as to be reused for an SOI layer wafer 11 of the bonded SOI wafer 10, comprises: rapidly heating the layer transferred wafer 11b in an oxidizing atmosphere, then holding it for a fixed time and subsequently rapidly cooling it; and mirror-polishing a surface of the layer transferred wafer 11b.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: A bonded wafer is produced by a method comprising a step of implanting ions of a light element such as hydrogen, helium or the like into a wafer for active layer at a predetermined depth position to form an ion implanted layer, a step of bonding the wafer for active layer to a wafer for support substrate through an insulating film, a step of exfoliating the wafer at the ion implanted layer, a first heat treatment step of conducting a sacrificial oxidation for reducing damage on a surface of an active layer exposed through the exfoliation and a second heat treatment step of raising a bonding strength, in which the second heat treatment step is continuously conducted after the first heat treatment step without removing an oxide film formed on the surface of the active layer.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: This method for heat-treating a silicon wafer includes: a step of subjecting a silicon wafer to a high-temperature heat treatment in an ambient gas atmosphere of hydrogen gas, argon gas or a mixture thereof; and a step of lowering a temperature at a rate of 2° C./min or less in a nitrogen-gas-containing ambient atmosphere in a portion or all of a process of lowering a temperature to a wafer removal temperature following said high-temperature heat treatment. This silicon wafer has a defect-free layer which is formed by a high-temperature heat treatment and is included in a surface thereof, wherein an average iron concentration in said surface is 1×1010 atoms/cm3 or less.

Abstract: The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness.

Abstract: This p-type silicon wafer was subjected to heat treatment to have a resistivity of 10 ?·cm or more, a BMD density of 5×107 defects/cm3 or more, and an n-type impurity concentration of 1×1014 atoms/cm3 or less at a depth of within 5 ?m from a surface of the wafer. This method for heat-treating p-type silicon wafers, the method includes the steps of: loading p-type silicon wafers onto a wafer boat, inserting into a vertical furnace, and holding in an argon gas ambient atmosphere at a temperature of 1100 to 1300° C. for one hour; moving the wafer boat to a transfer chamber and discharging the silicon wafers; and transferring to the wafer boat silicon wafers to be heat treated next, wherein after the discharge of the heat-treated silicon wafers, the silicon wafers to be heat-treated next are transferred to the wafer boat within a waiting time of less than two hours.