Patents by Inventor AKITSUGU UEDA

AKITSUGU UEDA 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: 20240128096
    Abstract: A silicon semiconductor wafer is transported into a chamber, and preheating of the semiconductor wafer is started in a nitrogen atmosphere by irradiation with light from halogen lamps. When the temperature of the semiconductor wafer reaches a predetermined switching temperature in the course of the preheating, oxygen gas is supplied into the chamber to change the atmosphere within the chamber from the nitrogen atmosphere to an oxygen atmosphere. Thereafter, a front surface of the semiconductor wafer is heated for an extremely short time period by flash irradiation. Oxidation is suppressed when the temperature of the semiconductor wafer is relatively low below the switching temperature, and is caused after the temperature of the semiconductor wafer becomes relatively high. As a result, a dense, thin oxide film having good properties with fewer defects at an interface with a silicon base layer is formed on the front surface of the semiconductor wafer.
    Type: Application
    Filed: December 21, 2023
    Publication date: April 18, 2024
    Inventors: Akitsugu UEDA, Kazuhiko FUSE
  • Patent number: 11901200
    Abstract: A silicon semiconductor wafer is transported into a chamber, and preheating of the semiconductor wafer is started in a nitrogen atmosphere by irradiation with light from halogen lamps. When the temperature of the semiconductor wafer reaches a predetermined switching temperature in the course of the preheating, oxygen gas is supplied into the chamber to change the atmosphere within the chamber from the nitrogen atmosphere to an oxygen atmosphere. Thereafter, a front surface of the semiconductor wafer is heated for an extremely short time period by flash irradiation. Oxidation is suppressed when the temperature of the semiconductor wafer is relatively low below the switching temperature, and is caused after the temperature of the semiconductor wafer becomes relatively high. As a result, a dense, thin oxide film having good properties with fewer defects at an interface with a silicon base layer is formed on the front surface of the semiconductor wafer.
    Type: Grant
    Filed: March 4, 2022
    Date of Patent: February 13, 2024
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Akitsugu Ueda, Kazuhiko Fuse
  • Patent number: 11798823
    Abstract: A gas ring is attached to an upper portion of a chamber side portion as a side wall of a chamber. The gas ring is formed by overlapping an upper ring and a lower ring. A gap between the upper ring and the lower ring provides a flow path for processing gas. A labyrinthine resisting unit is formed in the flow path. The mass of the lower ring having an inner wall surface is increased to increase heat capacity. The lower ring is attached to the chamber side portion to be in surface contact with the chamber side portion, so that thermal conductivity from the lower ring to the chamber side portion has a large value, and the amount of heat accumulated in the lower ring is reduced. An increase in temperature of the lower ring at thermal processing is thereby suppressed to prevent discoloration of the gas ring.
    Type: Grant
    Filed: October 21, 2020
    Date of Patent: October 24, 2023
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Hiroshi Miyake, Kazuhiko Fuse, Akitsugu Ueda
  • Patent number: 11621178
    Abstract: When pressure in a chamber is brought to atmospheric pressure and the chamber is filled with an inert gas atmosphere, the atmosphere in the chamber is sucked into an oxygen concentration analyzer through a sampling line such that oxygen concentration in the chamber is measured by the oxygen concentration analyzer. When the pressure in the chamber is reduced to less than atmospheric pressure, nitrogen gas is supplied to the oxygen concentration analyzer through an inert gas supply line simultaneously with suspending the measurement of oxygen concentration in the chamber. Even when the measurement of oxygen concentration in the chamber is suspended, reverse flow to the oxygen concentration analyzer from a gas exhaust pipe can be prevented, and the oxygen concentration analyzer can be prevented from being exposed to exhaust from the chamber. The configuration results in maintaining measurement accuracy of the oxygen concentration analyzer in a low oxygen concentration range.
    Type: Grant
    Filed: January 24, 2019
    Date of Patent: April 4, 2023
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Takayuki Aoyama, Akitsugu Ueda, Mao Omori, Kazunori Amago
  • Patent number: 11574824
    Abstract: A semiconductor wafer to be treated is heated at a first preheating temperature ranging from 100 to 200° C. while a pressure in a chamber housing the semiconductor wafer is reduced to a pressure lower than an atmospheric pressure. After the semiconductor wafer is preheated to increase the temperature into a second preheating temperature ranging from 500 to 700° C. while the pressure in the chamber is restored to a pressure higher than the reduced pressure, a flash lamp emits a flashlight to a surface of the semiconductor wafer. Heating the semiconductor wafer at the first preheating temperature that is a relatively low temperature enables, for example, the moisture absorbed on the surface of the semiconductor wafer in trace amounts to be desorbed from the surface, and also enables the flash heating treatment to be performed with oxygen derived from such absorption removed as much as possible.
    Type: Grant
    Filed: April 4, 2017
    Date of Patent: February 7, 2023
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Takayuki Aoyama, Shinichi Kato, Kazuhiko Fuse, Hikaru Kawarazaki, Masashi Furukawa, Hideaki Tanimura, Akitsugu Ueda
  • Publication number: 20220189799
    Abstract: A silicon semiconductor wafer is transported into a chamber, and preheating of the semiconductor wafer is started in a nitrogen atmosphere by irradiation with light from halogen lamps. When the temperature of the semiconductor wafer reaches a predetermined switching temperature in the course of the preheating, oxygen gas is supplied into the chamber to change the atmosphere within the chamber from the nitrogen atmosphere to an oxygen atmosphere. Thereafter, a front surface of the semiconductor wafer is heated for an extremely short time period by flash irradiation. Oxidation is suppressed when the temperature of the semiconductor wafer is relatively low below the switching temperature, and is caused after the temperature of the semiconductor wafer becomes relatively high. As a result, a dense, thin oxide film having good properties with fewer defects at an interface with a silicon base layer is formed on the front surface of the semiconductor wafer.
    Type: Application
    Filed: March 4, 2022
    Publication date: June 16, 2022
    Inventors: Akitsugu UEDA, Kazuhiko FUSE
  • Patent number: 11322375
    Abstract: A silicon semiconductor wafer is transported into a chamber, and preheating of the semiconductor wafer is started in a nitrogen atmosphere by irradiation with light from halogen lamps. When the temperature of the semiconductor wafer reaches a predetermined switching temperature in the course of the preheating, oxygen gas is supplied into the chamber to change the atmosphere within the chamber from the nitrogen atmosphere to an oxygen atmosphere. Thereafter, a front surface of the semiconductor wafer is heated for an extremely short time period by flash irradiation. Oxidation is suppressed when the temperature of the semiconductor wafer is relatively low below the switching temperature, and is caused after the temperature of the semiconductor wafer becomes relatively high. As a result, a dense, thin oxide film having good properties with fewer defects at an interface with a silicon base layer is formed on the front surface of the semiconductor wafer.
    Type: Grant
    Filed: December 26, 2019
    Date of Patent: May 3, 2022
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Akitsugu Ueda, Kazuhiko Fuse
  • Patent number: 11282708
    Abstract: Performed is a hydrogen anneal of heating a semiconductor wafer on which a thin film containing a dopant and carbon is formed to an anneal temperature in an atmosphere containing hydrogen. Subsequently, a hydrogen atmosphere in a chamber is replaced with an oxygen atmosphere, and the semiconductor wafer is preheated to a preheating temperature in the oxygen atmosphere. Performed then is a flash heating treatment of heating a surface of the semiconductor wafer to a peak temperature for less than one second. The semiconductor wafer is heated in the oxygen atmosphere, thus activation of dopant and binding of carbon in the thin film and oxygen in the atmosphere are promoted, and carbon is exhausted from the thin film to prevent hardening of the thin film. As a result, the thin film containing carbon can be easily peeled from the semiconductor wafer.
    Type: Grant
    Filed: April 2, 2020
    Date of Patent: March 22, 2022
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Akitsugu Ueda, Kazuhiko Fuse
  • Publication number: 20220076970
    Abstract: A light diffusion plate is placed on an upper surface of an upper chamber window. A blasting process is applied to a lower surface of the light diffusion plate to provide the lower surface in the form of frosted glass. When the light diffusion plate is placed on the upper surface of the upper chamber window, the light diffusion plate and the upper chamber window do not closely adhere to each other. The frosted glass releases a mass of air entering between contact surfaces of the light diffusion plate and the upper chamber window to the outside even if the mass of air thermally expands during heat treatment. This restrains the occurrence of a phenomenon in which a thin layer of air is trapped between the light diffusion plate and the upper chamber window to prevent the sliding of the light diffusion plate resulting from the air layer.
    Type: Application
    Filed: September 2, 2021
    Publication date: March 10, 2022
    Inventors: Akitsugu UEDA, Hiroshi MIYAKE, Kazuhiko FUSE, Hideaki TANIMURA
  • Publication number: 20210151335
    Abstract: A gas ring is attached to an upper portion of a chamber side portion as a side wall of a chamber. The gas ring is formed by overlapping an upper ring and a lower ring. A gap between the upper ring and the lower ring provides a flow path for processing gas. A labyrinthine resisting unit is formed in the flow path. The mass of the lower ring having an inner wall surface is increased to increase heat capacity. The lower ring is attached to the chamber side portion to be in surface contact with the chamber side portion, so that thermal conductivity from the lower ring to the chamber side portion has a large value, and the amount of heat accumulated in the lower ring is reduced. An increase in temperature of the lower ring at thermal processing is thereby suppressed to prevent discoloration of the gas ring.
    Type: Application
    Filed: October 21, 2020
    Publication date: May 20, 2021
    Inventors: Hiroshi MIYAKE, Kazuhiko FUSE, Akitsugu UEDA
  • Publication number: 20200328083
    Abstract: Performed is a hydrogen anneal of heating a semiconductor wafer on which a thin film containing a dopant and carbon is formed to an anneal temperature in an atmosphere containing hydrogen. Subsequently, a hydrogen atmosphere in a chamber is replaced with an oxygen atmosphere, and the semiconductor wafer is preheated to a preheating temperature in the oxygen atmosphere. Performed then is a flash heating treatment of heating a surface of the semiconductor wafer to a peak temperature for less than one second. The semiconductor wafer is heated in the oxygen atmosphere, thus activation of dopant and binding of carbon in the thin film and oxygen in the atmosphere are promoted, and carbon is exhausted from the thin film to prevent hardening of the thin film. As a result, the thin film containing carbon can be easily peeled from the semiconductor wafer.
    Type: Application
    Filed: April 2, 2020
    Publication date: October 15, 2020
    Inventors: Akitsugu Ueda, Kazuhiko Fuse
  • Publication number: 20200286756
    Abstract: A silicon semiconductor wafer is transported into a chamber, and preheating of the semiconductor wafer is started in a nitrogen atmosphere by irradiation with light from halogen lamps. When the temperature of the semiconductor wafer reaches a predetermined switching temperature in the course of the preheating, oxygen gas is supplied into the chamber to change the atmosphere within the chamber from the nitrogen atmosphere to an oxygen atmosphere. Thereafter, a front surface of the semiconductor wafer is heated for an extremely short time period by flash irradiation. Oxidation is suppressed when the temperature of the semiconductor wafer is relatively low below the switching temperature, and is caused after the temperature of the semiconductor wafer becomes relatively high. As a result, a dense, thin oxide film having good properties with fewer defects at an interface with a silicon base layer is formed on the front surface of the semiconductor wafer.
    Type: Application
    Filed: December 26, 2019
    Publication date: September 10, 2020
    Inventors: Akitsugu UEDA, Kazuhiko FUSE
  • Publication number: 20200266084
    Abstract: A semiconductor wafer transport mode of a heat treatment apparatus is switchable between two modes of a “high throughput mode” and a “low oxygen concentration mode” as appropriate. In the “low oxygen concentration mode”, a first cooling chamber is used only as a path for transferring the semiconductor wafer, and a second cooling chamber is used only as a dedicated cooling unit for cooling the semiconductor wafer subjected to flash heating. On the other hand, in the “high throughput mode”, both of the first cooling chamber and the second cooling chamber are used as paths for transferring the semiconductor wafer, and as the cooling units, too.
    Type: Application
    Filed: April 22, 2020
    Publication date: August 20, 2020
    Inventors: Takayuki AOYAMA, Shinichi IKEDA, Akitsugu UEDA
  • Patent number: 10580667
    Abstract: A heat treatment apparatus is provided with two cool chambers, that is, a first cool chamber and a second cool chamber. A semiconductor wafer before treatment is alternately carried into the first cool chamber or the second cool chamber and then transported to a heat treatment part by a transport robot after a nitrogen purge is performed. The semiconductor wafer after being heat-treated in the heat treatment part is alternately transported to the first cool chamber or the second cool chamber to be cooled. A sufficient cooling time is secured for the independent semiconductor wafer, and a reduction in throughput as the whole heat treatment apparatus can be suppressed.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: March 3, 2020
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Takayuki Aoyama, Yasuaki Kondo, Shinji Miyawaki, Shinichi Kato, Kazuhiko Fuse, Hideaki Tanimura, Akitsugu Ueda, Hikaru Kawarazaki, Masashi Furukawa
  • Publication number: 20190267262
    Abstract: When pressure in a chamber is brought to atmospheric pressure and the chamber is filled with an inert gas atmosphere, the atmosphere in the chamber is sucked into an oxygen concentration analyzer through a sampling line such that oxygen concentration in the chamber is measured by the oxygen concentration analyzer. When the pressure in the chamber is reduced to less than atmospheric pressure, nitrogen gas is supplied to the oxygen concentration analyzer through an inert gas supply line simultaneously with suspending the measurement of oxygen concentration in the chamber. Even when the measurement of oxygen concentration in the chamber is suspended, reverse flow to the oxygen concentration analyzer from a gas exhaust pipe can be prevented, and the oxygen concentration analyzer can be prevented from being exposed to exhaust from the chamber. The configuration results in maintaining measurement accuracy of the oxygen concentration analyzer in a low oxygen concentration range.
    Type: Application
    Filed: January 24, 2019
    Publication date: August 29, 2019
    Inventors: Takayuki AOYAMA, Akitsugu UEDA, Mao OMORI, Kazunori AMAGO
  • Patent number: 10319616
    Abstract: An untreated semiconductor wafer is transferred from an indexer unit to a treatment chamber via a first cool chamber and a transfer chamber in this order. A treated semiconductor wafer subjected to heating treatment in the treatment chamber is transferred to the indexer unit via the transfer chamber and the first cool chamber in this order. For a predetermined time after an untreated semiconductor wafer is transferred into the first cool chamber, nitrogen gas is supplied into the first cool chamber at a large supply flow rate and exhausting from the first cool chamber is performed at a large exhaust flow rate. An oxygen concentration in the first cool chamber sharply decreases to enable the semiconductor wafer after the heating treatment to be prevented from being oxidized.
    Type: Grant
    Filed: February 27, 2018
    Date of Patent: June 11, 2019
    Assignee: Screen Holdings Co., Ltd.
    Inventor: Akitsugu Ueda
  • Publication number: 20190164789
    Abstract: A semiconductor wafer to be treated is heated at a first preheating temperature ranging from 100 to 200° C. while a pressure in a chamber housing the semiconductor wafer is reduced to a pressure lower than an atmospheric pressure. After the semiconductor wafer is preheated to increase the temperature into a second preheating temperature ranging from 500 to 700° C. while the pressure in the chamber is restored to a pressure higher than the reduced pressure, a flash lamp emits a flashlight to a surface of the semiconductor wafer. Heating the semiconductor wafer at the first preheating temperature that is a relatively low temperature enables, for example, the moisture absorbed on the surface of the semiconductor wafer in trace amounts to be desorbed from the surface, and also enables the flash heating treatment to be performed with oxygen derived from such absorption removed as much as possible.
    Type: Application
    Filed: April 4, 2017
    Publication date: May 30, 2019
    Inventors: Takayuki AOYAMA, Shinichi KATO, Kazuhiko FUSE, Hikaru KAWARAZAKI, Masashi FURUKAWA, Hideaki TANIMURA, Akitsugu UEDA
  • Publication number: 20190006215
    Abstract: A semiconductor wafer transport mode of a heat treatment apparatus is switchable between two modes of a “high throughput mode” and a “low oxygen concentration mode” as appropriate. In the “low oxygen concentration mode”, a first cooling chamber is used only as a path for transferring the semiconductor wafer, and a second cooling chamber is used only as a dedicated cooling unit for cooling the semiconductor wafer subjected to flash heating. On the other hand, in the “high throughput mode”, both of the first cooling chamber and the second cooling chamber are used as paths for transferring the semiconductor wafer, and as the cooling units, too.
    Type: Application
    Filed: June 25, 2018
    Publication date: January 3, 2019
    Inventors: Takayuki AOYAMA, Shinichi IKEDA, Akitsugu UEDA
  • Publication number: 20180261478
    Abstract: An untreated semiconductor wafer is transferred from an indexer unit to a treatment chamber via a first cool chamber and a transfer chamber in this order. A treated semiconductor wafer subjected to heating treatment in the treatment chamber is transferred to the indexer unit via the transfer chamber and the first cool chamber in this order. For a predetermined time after an untreated semiconductor wafer is transferred into the first cool chamber, nitrogen gas is supplied into the first cool chamber at a large supply flow rate and exhausting from the first cool chamber is performed at a large exhaust flow rate. An oxygen concentration in the first cool chamber sharply decreases to enable the semiconductor wafer after the heating treatment to be prevented from being oxidized.
    Type: Application
    Filed: February 27, 2018
    Publication date: September 13, 2018
    Inventor: Akitsugu UEDA
  • Publication number: 20180202071
    Abstract: A hafnium oxide film is deposited on a front surface of a substrate across a boundary layer film. By preheating the substrate on which the hafnium oxide film is formed, and then, irradiating the front surface of the substrate with intense flash light over an extremely short radiation time, only the front surface of the substrate is instantaneously heated and is rapidly thermally expanded. At this instant, a strong compressive stress is applied to the front surface of the substrate, and a tensile stress is applied to a back surface. By heating the hafnium oxide film and applying a strong compressive stress to the hafnium oxide film at the same time, the proportion of a cubic structure in a crystal structure of the hafnium oxide film can be increased, and the crystal structure occurring in the hafnium oxide film can be adjusted.
    Type: Application
    Filed: December 21, 2017
    Publication date: July 19, 2018
    Inventors: Hikaru Kawarazaki, Akitsugu Ueda