Patents by Inventor Kazuhiko Fuse

Kazuhiko Fuse 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).

  • Patent number: 11004693
    Abstract: A plurality of flash lamps that irradiate a semiconductor wafer with flash light are arrayed in a plane. The array of the plurality of flash lamps is divided into two zones: a central zone including a region opposed to a central portion of the semiconductor wafer to be treated, and a peripheral zone outside the central zone. During flash light irradiation, an emission time of a flash lamp belonging to the peripheral zone is set to be longer than an emission time of a flash lamp belonging to the central zone. Thus, a greater amount of flash light is applied to the peripheral portion of the semiconductor wafer, where a temperature drop is relatively likely to occur, than to the central portion thereof, thus preventing a relative temperature drop in the peripheral portion of the semiconductor wafer during flash heating.
    Type: Grant
    Filed: May 5, 2016
    Date of Patent: May 11, 2021
    Assignee: SCREEN Holdings Co., Ltd.
    Inventor: Kazuhiko Fuse
  • Patent number: 10978319
    Abstract: Over a front surface of a silicon semiconductor wafer is deposited a high dielectric constant film with a silicon oxide film, serving as an interface layer, provided between the semiconductor wafer and the high dielectric constant film. After a chamber houses the semiconductor wafer, a chamber's pressure is reduced to be lower than atmospheric pressure. Subsequently, a gaseous mixture of ammonia and nitrogen gas is supplied into the chamber to return the pressure to ordinary pressure, and the front surface is irradiated with a flash light, thereby performing post deposition annealing (PDA) on the high dielectric constant film. Since the pressure is reduced once to be lower than atmospheric pressure and then returned to ordinary pressure, a chamber's oxygen concentration is lowered remarkably during the PDA. This restricts an increase in thickness of the silicon oxide film underlying the high dielectric constant film by oxygen taken in during the PDA.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: April 13, 2021
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Takayuki Aoyama, Hikaru Kawarazaki, Masashi Furukawa, Shinichi Kato, Kazuhiko Fuse, Hideaki Tanimura
  • Patent number: 10950472
    Abstract: A ring support is attached to an inner wall surface of a chamber that houses a semiconductor wafer to support a susceptor. When the semiconductor wafer is placed on the susceptor, an inner space of the chamber is separated into an upper space and a lower space. Particles are likely to accumulate on a lower chamber window as a floor part of the chamber. However, since the upper space and the lower space are separated, the semiconductor wafer can be prevented from being contaminated by the particles flowing into the upper space and adhering to a surface of the semiconductor wafer even when the particles on the lower chamber window are blown up by irradiation with flash light.
    Type: Grant
    Filed: July 13, 2017
    Date of Patent: March 16, 2021
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Takahiro Yamada, Makoto Abe, Kazuhiko Fuse, Jun Watanabe, Shinji Miyawaki
  • Publication number: 20210051771
    Abstract: As treatment of a semiconductor wafer to be a product proceeds in a heat treatment apparatus, contaminants adhere to an inner wall surface of a chamber. After the treatment of the semiconductor wafer is completed, a gas containing ozone is supplied into the chamber to form an atmosphere containing ozone. While the atmosphere containing ozone is heated by irradiation with light from a halogen lamp, a flash lamp emits a flash of light containing ultraviolet light. The ultraviolet light decomposes ozone to generate active oxygen, and the active oxygen reacts with the contaminants to decompose and remove the contaminants from the inner wall surface of the chamber. The contaminants decomposed and vaporized are discharged out of the chamber by exhausting the atmosphere in the chamber.
    Type: Application
    Filed: August 7, 2020
    Publication date: February 18, 2021
    Inventor: Kazuhiko FUSE
  • Patent number: 10879072
    Abstract: First irradiation which causes an emission output from a flash lamp to reach its maximum value over a time period in the range of 1 to 20 milliseconds is performed to increase the temperature of a front surface of a semiconductor wafer from a preheating temperature to a target temperature for a time period in the range of 1 to 20 milliseconds. This achieves the activation of the impurities. Subsequently, second irradiation which gradually decreases the emission output from the maximum value over a time period in the range of 3 to 50 milliseconds is performed to maintain the temperature of the front surface within a ±25° C. range around the target temperature for a time period in the range of 3 to 50 milliseconds. This prevents the occurrence of process-induced damage while suppressing the diffusion of the impurities.
    Type: Grant
    Filed: March 11, 2019
    Date of Patent: December 29, 2020
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Kazuhiko Fuse, Shinichi Kato, Kenichi Yokouchi
  • 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
  • Patent number: 10790171
    Abstract: Over a front surface of a silicon semiconductor wafer is deposited a high dielectric constant film with a silicon oxide film, serving as an interface layer, provided between the semiconductor wafer and the high dielectric constant film. After a chamber houses the semiconductor wafer, a chamber's pressure is reduced to be lower than atmospheric pressure. Subsequently, a gaseous mixture of ammonia and nitrogen gas is supplied into the chamber to return the pressure to ordinary pressure, and the front surface is irradiated with a flash light, thereby performing post deposition annealing (PDA) on the high dielectric constant film. Since the pressure is reduced once to be lower than atmospheric pressure and then returned to ordinary pressure, a chamber's oxygen concentration is lowered remarkably during the PDA. This restricts an increase in thickness of the silicon oxide film underlying the high dielectric constant film by oxygen taken in during the PDA.
    Type: Grant
    Filed: June 25, 2019
    Date of Patent: September 29, 2020
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Takayuki Aoyama, Hikaru Kawarazaki, Masashi Furukawa, Shinichi Kato, Kazuhiko Fuse, Hideaki Tanimura
  • Patent number: 10784127
    Abstract: A pyrometer holder is mounted to an outer wall of a chamber while holding a lower radiation thermometer. The front end of the lower radiation thermometer is brought into abutment with a mounting portion of the pyrometer holder, and a bottom plate is brought into abutment with the rear end of the lower radiation thermometer. A tension spring is tensioned between the bottom plate and the mounting portion to prevent the lower radiation thermometer from falling off or misregistration. An angle adjusting mechanism adjusts the angle of the radiation thermometer with respect to the outer wall of the chamber, with the front end of the radiation thermometer serving as a supporting point. Thus, the measurement position of the lower radiation thermometer is adjusted.
    Type: Grant
    Filed: February 26, 2018
    Date of Patent: September 22, 2020
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Kazuhiko Fuse, Shinji Miyawaki, Takahiro Kitazawa
  • Patent number: 10777415
    Abstract: Hydrogen annealing for heating a semiconductor wafer on which a thin film containing a dopant is deposited to an annealing temperature under an atmosphere containing hydrogen is performed. A native oxide film is inevitably formed between the thin film containing the dopant and the semiconductor wafer, however, by performing hydrogen annealing, the dopant atoms diffuse relatively easily in the native oxide film and accumulate at the interface between the front surface of the semiconductor wafer and the native oxide film. Subsequently, the semiconductor wafer is preheated to a preheating temperature under a nitrogen atmosphere, and then, flash heating treatment in which the front surface of the semiconductor wafer is heated to a peak temperature for less than one second is performed. The dopant atoms are diffused and activated in a shallow manner from the front surface of the semiconductor wafer, thus, the low-resistance and extremely shallow junction is obtained.
    Type: Grant
    Filed: December 26, 2018
    Date of Patent: September 15, 2020
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Kazuhiko Fuse, Hikaru Kawarazaki, Hideaki Tanimura, Shinichi Kato
  • 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
  • Patent number: 10643850
    Abstract: A PSG film, which is a silicon dioxide thin film containing phosphorus as a dopant, is formed on the surface of a semiconductor wafer. The semiconductor wafer having the PSG film formed thereon is kept at a predetermined heating temperature by light radiation from halogen lamps in the atmosphere containing hydrogen for 1 second or longer, so that the dopant is diffused from the PSG film into the surface of the semiconductor wafer. In addition, the flashing light is radiated to the semiconductor wafer for the radiation time shorter than 1 second to heat the surface of the semiconductor wafer to the target temperature so as to activate the dopant. When the PSG film is heated in the atmosphere containing hydrogen, a diffusion coefficient of the dopant contained in the PSG film becomes high; therefore, the dopant can be efficiently diffused from the PSG film into the semiconductor wafer.
    Type: Grant
    Filed: November 16, 2017
    Date of Patent: May 5, 2020
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Hideaki Tanimura, Takayuki Aoyama, Kazuhiko Fuse, Takahiro Yamada
  • Patent number: 10643869
    Abstract: A semiconductor wafer that has a plane orientation of (100) and is made of monocrystalline silicon is warped along an axis, i.e., a diameter along a <100> direction of the semiconductor wafer when irradiated with a flash of light. The semiconductor wafer is placed on a susceptor while the direction of the semiconductor wafer is adjusted so that the diameter along the <100> direction coincides with an optical axis of an upper radiation thermometer. This adjustment makes a diameter along a direction in which a warp of the semiconductor wafer is smallest during irradiation with a flash of light coincide with the optical axis of the upper radiation thermometer. As a result, the semiconductor wafer is hardly warped along the optical axis direction of the upper radiation thermometer even during irradiation with a flash of light, thus hardly changing the emissivity of the semiconductor wafer, so that it is possible to accurately measure the temperature of an upper surface of the semiconductor wafer.
    Type: Grant
    Filed: January 11, 2018
    Date of Patent: May 5, 2020
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Takahiro Kitazawa, Kazuhiko Fuse
  • Patent number: 10636676
    Abstract: When pressure in a chamber is once reduced lower than that when a flash of light is emitted and is maintained, after a flash lamp irradiates a semiconductor wafer accommodated in the chamber with the flash of light, a portion in the chamber, where gas is liable to remain, is eliminated. Then, when a flow rate of nitrogen gas to be supplied into the chamber is increased to discharge gas in the chamber, particles flying in the chamber due to flash irradiation can be smoothly discharged. As a result, the particles flying in the chamber can be prevented from being attached to an additional semiconductor wafer.
    Type: Grant
    Filed: January 29, 2018
    Date of Patent: April 28, 2020
    Assignee: SCREEN HOLDINGS CO., LTD.
    Inventors: Yukio Ono, Kaoru Matsuo, Kazuhiko Fuse
  • Publication number: 20200098600
    Abstract: Dummy running is carried out which performs preheating treatment using halogen lamps and flash heating treatment using flash lamps on a dummy wafer to control the temperature of in-chamber structures including a susceptor and the like. In this process, a wear-and-tear value is calculated by adding up the amounts of electric power inputted to the halogen lamps or the like each time the preheating treatment or the flash heating treatment is performed. The wear-and-tear value is an indicator indicating the degree of deterioration of the dummy wafer. If the wear-and-tear value of the dummy wafer is not less than a predetermined threshold value, an alarm is issued. This allows an operator of a heat treatment apparatus to recognize that the deterioration of the dummy wafer reaches a limit value and to reliably grasp the dummy wafer suffering advanced deterioration.
    Type: Application
    Filed: July 24, 2019
    Publication date: March 26, 2020
    Inventors: Tomohiro Ueno, Kazuhiko Fuse, Mao Omori
  • Publication number: 20200098601
    Abstract: Dummy running is carried out which performs preheating treatment using halogen lamps and flash heating treatment using flash lamps on a dummy wafer to control the temperature of in-chamber structures including a susceptor and the like. In this process, a preheating counter or a flash heating counter is incremented each time the preheating treatment or the flash heating treatment is performed. An alarm is issued, if the preheating counter or the flash heating counter that is a wear-and-tear value of the dummy wafer is not less than a predetermined threshold value. This allows an operator of a heat treatment apparatus to recognize that the deterioration of the dummy wafer reaches a limit value, thereby preventing the erroneous treatment of a dummy wafer suffering advanced deterioration.
    Type: Application
    Filed: July 23, 2019
    Publication date: March 26, 2020
    Inventors: Tomohiro Ueno, Kazuhiko FUSE, Mao OMORI
  • Publication number: 20200090949
    Abstract: When a carrier storing a plurality of dummy wafers therein is transported into a heat treatment apparatus, the carrier is registered as a dummy carrier exclusive to the dummy wafers. A dummy database in which a treatment history of each of the dummy wafers is associated with the carrier is held in a storage part. The treatment history of each of the dummy wafers registered in the dummy database is displayed on a display part of the heat treatment apparatus. An operator of the heat treatment apparatus views the displayed information to thereby appropriately grasp and manage the treatment history of each of the dummy wafers.
    Type: Application
    Filed: July 22, 2019
    Publication date: March 19, 2020
    Inventors: Tomohiro Ueno, Kazuhiko Fuse, Mao Omori
  • 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
  • Patent number: 10573569
    Abstract: A substrate in a chamber is preheated through light irradiation by a halogen lamp and then heated through irradiation with flash light from a flash lamp. Ammonia is supplied to the chamber from an ammonia supply mechanism to form ammonia atmosphere. The temperature of the substrate at heating processing is measured by a radiation thermometer. When the measurement wavelength band of the radiation thermometer overlaps with the absorption wavelength band of ammonia, the set emissivity of the radiation thermometer is changed and set to be lower than the actual emissivity of the substrate. When radiation light emitted from the substrate is absorbed by the ammonia atmosphere, the radiation thermometer can accurately output the temperature of the substrate as a measured value by reducing the set emissivity of the radiation thermometer.
    Type: Grant
    Filed: February 20, 2019
    Date of Patent: February 25, 2020
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Masashi Furukawa, Hikaru Kawarazaki, Kazuhiko Fuse
  • Publication number: 20190311924
    Abstract: Over a front surface of a silicon semiconductor wafer is deposited a high dielectric constant film with a silicon oxide film, serving as an interface layer, provided between the semiconductor wafer and the high dielectric constant film. After a chamber houses the semiconductor wafer, a chamber's pressure is reduced to be lower than atmospheric pressure. Subsequently, a gaseous mixture of ammonia and nitrogen gas is supplied into the chamber to return the pressure to ordinary pressure, and the front surface is irradiated with a flash light, thereby performing post deposition annealing (PDA) on the high dielectric constant film. Since the pressure is reduced once to be lower than atmospheric pressure and then returned to ordinary pressure, a chamber's oxygen concentration is lowered remarkably during the PDA. This restricts an increase in thickness of the silicon oxide film underlying the high dielectric constant film by oxygen taken in during the PDA.
    Type: Application
    Filed: June 25, 2019
    Publication date: October 10, 2019
    Inventors: Takayuki AOYAMA, Hikaru KAWARAZAKI, Masashi FURUKAWA, Shinichi KATO, Kazuhiko FUSE, Hideaki TANIMURA
  • Patent number: 10424483
    Abstract: A metal film is deposited on a front surface of a semiconductor wafer of silicon. After the semiconductor wafer is received in a chamber, the pressure in the chamber is reduced to a pressure lower than atmospheric pressure. Thereafter, nitrogen gas is supplied into the chamber to return the pressure in the chamber to ordinary pressure, and the front surface of the semiconductor wafer is irradiated with a flash of light, so that a silicide that is a compound of the metal film and silicon is formed. The oxygen concentration in the chamber is significantly lowered during the formation of the silicide because the pressure in the chamber is reduced once to the pressure lower than atmospheric pressure and then returned to the ordinary pressure. This suppresses the increase in resistance of the silicide resulting from the entry of oxygen in the atmosphere in the chamber into defects near the interface between the metal film and a base material.
    Type: Grant
    Filed: December 3, 2018
    Date of Patent: September 24, 2019
    Assignee: SCREEN Holdings Co., Ltd.
    Inventors: Takayuki Aoyama, Hikaru Kawarazaki, Masashi Furukawa, Kazuhiko Fuse, Hideaki Tanimura, Shinichi Kato