Patents by Inventor Hiroji Aga

Hiroji Aga has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230154761
    Abstract: A method for manufacturing an SOI wafer including a step of performing an adjustment to a film thickness of an SOI layer of the SOI wafer by wet etching. In the step of performing the adjustment to the film thickness of the SOI layer, a first etching step of etching a surface of the SOI layer using an SC1 solution; and a second etching step of etching the surface of the SOI layer by bringing the SOI layer into contact with ozone water to form an oxide film on the surface of the SOI layer and then bringing the formed oxide film into contact with an HF-containing aqueous solution to remove the oxide film, are performed in combination. The etchings are performed such that a removal amount of the SOI layer in the first etching step is smaller than that in the second etching step.
    Type: Application
    Filed: April 14, 2021
    Publication date: May 18, 2023
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji AGA, Isao YOKOKAWA
  • Patent number: 11244851
    Abstract: A method for manufacturing an SOI wafer by performing a sacrificial oxidation treatment and reducing a thickness of an SOI layer of the SOI wafer, in which: the SOI wafer on which the sacrificial oxidation treatment is performed has a film thickness distribution with a one-way sloping shape; a thermal oxidation in the sacrificial oxidation treatment is performed by combining a non-rotating oxidation and a rotating oxidation, using a vertical heat treatment furnace; whereby a thermal oxide film having an oxide film thickness distribution with a one-way sloping shape canceling the film thickness distribution with a one-way sloping shape of the SOI layer, is formed on a surface of the SOI layer; and by removing the formed thermal oxide film, an SOI wafer having an SOI layer whose film thickness distribution with a one-way sloping shape has been resolved is manufactured.
    Type: Grant
    Filed: May 30, 2018
    Date of Patent: February 8, 2022
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Hiroji Aga
  • Publication number: 20200111701
    Abstract: A method for manufacturing an SOI wafer by performing a sacrificial oxidation treatment and reducing a thickness of an SOI layer of the SOI wafer, in which: the SOI wafer on which the sacrificial oxidation treatment is performed has a film thickness distribution with a one-way sloping shape; a thermal oxidation in the sacrificial oxidation treatment is performed by combining a non-rotating oxidation and a rotating oxidation, using a vertical heat treatment furnace; whereby a thermal oxide film having an oxide film thickness distribution with a one-way sloping shape canceling the film thickness distribution with a one-way sloping shape of the SOI layer, is formed on a surface of the SOI layer; and by removing the formed thermal oxide film, an SOI wafer having an SOI layer whose film thickness distribution with a one-way sloping shape has been resolved is manufactured.
    Type: Application
    Filed: May 30, 2018
    Publication date: April 9, 2020
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Hiroji AGA
  • Patent number: 10490440
    Abstract: Method for manufacturing bonded SOI wafer by bonding bond wafer and base wafer each composed of silicon single crystal with insulator film being interposed therebetween, including steps of: depositing polycrystalline silicon layer on bonding surface side of base wafer; polishing surface of polycrystalline silicon layer to obtain polished surface; forming thermal oxide film on polished surface; forming insulator film on bonding surface of bond wafer; bonding step of bonding bond and base wafers by bringing insulator and oxide films into close contact with each other; and thinning bonded bond wafer to form SOI layer, wherein silicon single crystal wafer having resistivity of 100 ?·cm or more is used as base wafer, thermal oxide film formed on polished surface has thickness of 15 nm or more with RMS of 0.6 nm or less, and any heat treatment after bonding step is performed with maximum treatment temperature of 1150° C. or less.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: November 26, 2019
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro Kobayashi, Hiroji Aga
  • Publication number: 20190221470
    Abstract: Method for manufacturing bonded SOI wafer by bonding bond wafer and base wafer each composed of silicon single crystal with insulator film being interposed therebetween, including steps of: depositing polycrystalline silicon layer on bonding surface side of base wafer; polishing surface of polycrystalline silicon layer to obtain polished surface; forming thermal oxide film on polished surface; forming insulator film on bonding surface of bond wafer; bonding step of bonding bond and base wafers by bringing insulator and oxide films into close contact with each other; and thinning bonded bond wafer to form SOI layer, wherein silicon single crystal wafer having resistivity of 100 ?·cm or more is used as base wafer, thermal oxide film formed on polished surface has thickness of 15 nm or more with RMS of 0.6 nm or less, and any heat treatment after bonding step is performed with maximum treatment temperature of 1150° C. or less.
    Type: Application
    Filed: April 25, 2017
    Publication date: July 18, 2019
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro KOBAYASHI, Hiroji AGA
  • Patent number: 10204824
    Abstract: A method for producing a SOI wafer that includes implanting at least one type of gas ion selected from a hydrogen ion and a rare gas ion from a surface of a bond wafer formed of a silicon single crystal to form an ion implanted layer, bonding the ion-implanted surface of the bond wafer to a surface of a base wafer formed of a silicon single crystal through a silicon oxide film formed on the base wafer surface, delaminating the bond wafer at the ion implanted layer by performing delamination heat treatment to fabricate a SOI wafer having a buried oxide film layer and a SOI layer on the base wafer, and performing flattening heat treatment on the SOI wafer in an atmosphere containing argon gas.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: February 12, 2019
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Isao Yokokawa, Hiroji Aga, Norihiro Kobayashi
  • Patent number: 10115580
    Abstract: A method for manufacturing an SOI wafer having SOI layer includes a thinning step to adjust SOI film thickness of the SOI wafer, including the steps of: (A1) measuring the SOI film thickness of the SOI wafer having the SOI layer before the thinning step; (A2) determining rotational position of the SOI wafer in the thinning step on the basis of a radial SOI film thickness distribution obtained in the measuring of the film thickness and previously determined radial stock removal distribution in the thinning step, and rotating the SOI wafer around the central axis thereof so as to bring the SOI wafer to the determined rotational position; and (A3) thinning the SOI layer of the rotated SOI wafer. The method for manufacturing the SOI wafer can produce an SOI wafer with an excellent radial film thickness uniformity of the SOI layer after the thinning step.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: October 30, 2018
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji Aga, Susumu Kuwabara
  • Publication number: 20180144975
    Abstract: A method for producing a SOI wafer that includes implanting at least one type of gas ion selected from a hydrogen ion and a rare gas ion from a surface of a bond wafer formed of a silicon single crystal to form an ion implanted layer, bonding the ion-implanted surface of the bond wafer to a surface of a base wafer formed of a silicon single crystal through a silicon oxide film formed on the base wafer surface, delaminating the bond wafer at the ion implanted layer by performing delamination heat treatment to fabricate a SOI wafer having a buried oxide film layer and a SOI layer on the base wafer, and performing flattening heat treatment on the SOI wafer in an atmosphere containing argon gas.
    Type: Application
    Filed: March 8, 2016
    Publication date: May 24, 2018
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Isao YOKOKAWA, Hiroji AGA, Norihiro KOBAYASHI
  • Patent number: 9953860
    Abstract: A method of manufacturing an SOI wafer, including (a) forming a thermal oxide film on an SOI layer of an SOI wafer by a heat treatment under an oxidizing gas atmosphere, (b) measuring thickness of the SOI layer after forming the thermal oxide film, (c) performing a batch cleaning, wherein an etching amount of SOI layer is adjusted depending on thickness of the SOI layer measured in step (b) such that thickness of the SOI layer is adjusted to be thicker than a target value after etching, (d) measuring thickness of the SOI layer after batch cleaning, (e) performing a single-wafer cleaning, wherein an etching amount of the SOI layer is adjusted depending on thickness of the SOI layer measured in step (d) such that thickness of the SOI layer is adjusted to be the target value after etching, and removing the thermal oxide film formed in step (a) before or after step (b).
    Type: Grant
    Filed: April 13, 2015
    Date of Patent: April 24, 2018
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Hiroji Aga
  • Patent number: 9865497
    Abstract: A method for manufacturing bonded wafer including: producing bonded wafer having thin-film on its base wafer by an ion implantation delamination method, and reducing film thickness of the thin-film, wherein the step of reducing the film thickness includes a stage of reducing the film thickness by sacrificial oxidation treatment or vapor phase etching, wherein the method for manufacturing bonded wafer further includes a cleaning step of cleaning the bonded wafer exposing the delamination surface just before the step of reducing the film thickness, wherein the cleaning step includes a stage of performing a wet cleaning by successively dipping the bonded wafer to plural of cleaning baths, and wherein the wet cleaning is performed without applying ultrasonic in each of the cleaning baths in the wet cleaning. The method enables to clean bonded wafer exposing delamination surface remaining damage of ion implantation using a cleaning line in a strict control level.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: January 9, 2018
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Isao Yokokawa, Hiroji Aga, Hiroshi Fujisawa
  • Patent number: 9859149
    Abstract: Method of producing bonded wafer including thin film on base wafer, including: implanting at least one gas ion selected from hydrogen ion and rare gas ion into bond wafer from surface of bond wafer to form layer of implanted ion; bonding surface from which ion is implanted into bond wafer and surface of base wafer directly or through insulator film; and then performing heat treatment to separate part of bond wafer along layer of implanted ion, wherein before bond wafer and base wafer are bonded, thickness of bond wafer and base wafer is measured, and combination of bond wafer and base wafer is selected such that difference in thickness between the wafers is less than 5 ?m, and selected bond and base wafers are bonded. This method can inhibit variation in thickness in marble pattern that occurs in thin film and produce bonded wafer including thin film with uniform thickness.
    Type: Grant
    Filed: May 19, 2014
    Date of Patent: January 2, 2018
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro Kobayashi, Hiroji Aga
  • Patent number: 9793154
    Abstract: The present invention is a method for manufacturing a bonded SOI wafer including: performing a thermal oxidation treatment including at least one of a thermal oxidation during temperature-rising and a thermal oxidation during temperature-falling with the use of a batch type heat treatment furnace, thereby forming a silicon oxide film in such a way that the oxide film buried in the delaminated bonded SOI wafer has a concentric oxide film thickness distribution, and subjecting the bonded SOI wafer after delaminating a bond wafer to a reducing heat treatment to make a film thickness range of the buried oxide film being smaller than a film thickness range before the reducing heat treatment. This provides a method for manufacturing a bonded SOI wafer which can suppress a variation of a radial distribution of a buried oxide film thickness caused by a reducing heat treatment performed after delaminating the SOI layer.
    Type: Grant
    Filed: February 9, 2015
    Date of Patent: October 17, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji Aga, Norihiro Kobayashi
  • Publication number: 20170287697
    Abstract: A method for manufacturing an SOI wafer having SOI layer includes a thinning step to adjust SOI film thickness of the SOI wafer, including the steps of: (A1) measuring the SOI film thickness of the SOI wafer having the SOI layer before the thinning step; (A2) determining rotational position of the SOI wafer in the thinning step on the basis of a radial SOI film thickness distribution obtained in the measuring of the film thickness and previously determined radial stock removal distribution in the thinning step, and rotating the SOI wafer around the central axis thereof so as to bring the SOI wafer to the determined rotational position; and (A3) thinning the SOI layer of the rotated SOI wafer. The method for manufacturing the SOI wafer can produce an SOI wafer with an excellent radial film thickness uniformity of the SOI layer after the thinning step.
    Type: Application
    Filed: August 28, 2015
    Publication date: October 5, 2017
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji AGA, Susumu KUWABARA
  • Patent number: 9773694
    Abstract: A method for manufacturing a bonded wafer, includes: ion-implanting a gas ion such as a hydrogen ion from a surface of a bond wafer, thereby forming an ion-implanted layer; bonding the bond wafer and a base wafer; producing a bonded wafer having a thin-film on the base wafer by delaminating the bond wafer along the ion-implanted layer; and performing an RTA treatment on the bonded wafer in a hydrogen gas-containing atmosphere; wherein a protective film is formed onto the surface of the thin-film in a heat treatment furnace in the course of temperature-falling from the maximum temperature of the RTA treatment before the bonded wafer is taken out from the heat treatment furnace; and then the bonded wafer with the protective film being formed thereon is taken out from the heat treatment furnace, and is then cleaned with a cleaning liquid which can etch the protective film and the thin-film.
    Type: Grant
    Filed: February 12, 2015
    Date of Patent: September 26, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro Kobayashi, Hiroji Aga
  • Publication number: 20170216992
    Abstract: A method for polishing a germanium wafer having a surface composed of germanium, including: adding aqueous hydrogen peroxide to a first polishing slurry of an aqueous alkaline solution containing colloidal silica to make a second polishing slurry, and polishing the surface of the germanium wafer by using the second polishing slurry; wherein the aqueous hydrogen peroxide is added to the first polishing slurry in a concentration such that 30 wt % aqueous hydrogen peroxide is added in a volume of more than 0 vol % and 0.1 vol % or less based on the volume of the first polishing slurry, and the polishing is performed by using the second polishing slurry. A method for polishing a germanium wafer that can make the surface roughness of a polished Ge surface be sufficiently small, and can sufficiently suppress generation of interface defects such as voids and blisters when used for a wafer to be bonded.
    Type: Application
    Filed: June 18, 2015
    Publication date: August 3, 2017
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Yasuo NAGAOKA, Hiroji AGA
  • Publication number: 20170200634
    Abstract: A method of manufacturing an SOI wafer, including (a) forming a thermal oxide film on an SOI layer of an SOI wafer by a heat treatment under an oxidizing gas atmosphere, (b) measuring thickness of the SOI layer after forming the thermal oxide film, (c) performing a batch cleaning, wherein an etching amount of SOI layer is adjusted depending on thickness of the SOI layer measured in step (b) such that thickness of the SOI layer is adjusted to be thicker than a target value after etching, (d) measuring thickness of the SOI layer after batch cleaning, (e) performing a single-wafer cleaning, wherein an etching amount of the SOI layer is adjusted depending on thickness of the SOI layer measured in step (d) such that thickness of the SOI layer is adjusted to be the target value after etching, and removing the thermal oxide film formed in step (a) before or after step (b).
    Type: Application
    Filed: April 13, 2015
    Publication date: July 13, 2017
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventor: Hiroji AGA
  • Patent number: 9679800
    Abstract: Method for manufacturing a bonded wafer, including implanting at least one gas ion into a bond wafer from a bond wafer surface forming an ion implantation layer, bonding the surface from the ion implantation into bond wafer and base wafer surface, and delaminating the bond wafer part along the ion implantation layer by heat treatment forming a bonded wafer having thin-film on the base wafer, wherein heat treatment is at most 400° C. to delaminate bond wafer part along the ion implantation layer, including measuring bond wafer thicknesses and base wafer, selecting a combination of bond and base wafers so difference between both wafers thicknesses is 5 ?m or more before bonding the bond and base wafers. Inhibition of film thickness unevenness with marble pattern caused in thin-film when a bonded wafer is manufactured by ion implantation delamination method, and can manufacture a bonded wafer having thin-film with high thickness uniformity.
    Type: Grant
    Filed: August 1, 2014
    Date of Patent: June 13, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Norihiro Kobayashi, Hiroji Aga
  • Patent number: 9673085
    Abstract: The present invention provides a method for manufacturing an SOI wafer including a step of forming an insulator film on an entire surface of a bond wafer before bonding, bringing a bonded wafer before delaminating the bond wafer at an ion implanted layer into contact with a liquid that enables dissolving the insulator film while protecting the insulator film on a back surface on the opposite side of a bonding surface of the bond wafer, or exposing the bonded wafer to a gas that enables dissolving the insulator film, and thus etching the insulator film placed between the bond wafer and a base wafer from an outer peripheral end of the bonded wafer toward a center of the bonded wafer.
    Type: Grant
    Filed: July 30, 2013
    Date of Patent: June 6, 2017
    Assignee: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji Aga, Toru Ishizuka
  • Publication number: 20160372363
    Abstract: The present invention is a method for manufacturing a bonded SOI wafer including: performing a thermal oxidation treatment including at least one of a thermal oxidation during temperature-rising and a thermal oxidation during temperature-falling with the use of a batch type heat treatment furnace, thereby forming a silicon oxide film in such a way that the oxide film buried in the delaminated bonded SOI wafer has a concentric oxide film thickness distribution, and subjecting the bonded SOI wafer after delaminating a bond wafer to a reducing heat treatment to make a film thickness range of the buried oxide film being smaller than a film thickness range before the reducing heat treatment. This provides a method for manufacturing a bonded SOT wafer which can suppress a variation of a radial distribution of a buried oxide film thickness caused by a reducing heat treatment performed after delaminating the SOI layer.
    Type: Application
    Filed: February 9, 2015
    Publication date: December 22, 2016
    Applicant: SHIN-ETSU HANDOTAI CO., LTD.
    Inventors: Hiroji AGA, Norihiro KOBAYASHI
  • Publication number: 20160365273
    Abstract: A method for manufacturing a bonded wafer, includes: ion-implanting a gas ion such as a hydrogen ion from a surface of a bond wafer, thereby forming an ion-implanted layer; bonding the bond wafer and a base wafer; producing a bonded wafer having a thin-film on the base wafer by delaminating the bond wafer along the ion-implanted layer; and performing an RTA treatment on the bonded wafer in a hydrogen gas-containing atmosphere; wherein a protective film is formed onto the surface of the thin-film in a heat treatment furnace in the course of temperature-falling from the maximum temperature of the RTA treatment before the bonded wafer is taken out from the heat treatment furnace; and then the bonded wafer with the protective film being formed thereon is taken out from the heat treatment furnace, and is then cleaned with a cleaning liquid which can etch the protective film and the thin-film.
    Type: Application
    Filed: February 12, 2015
    Publication date: December 15, 2016
    Applicant: Shin-Etsu Handotai Co., Ltd.
    Inventors: Norihiro KOBAYASHI, Hiroji AGA