Patents by Inventor Natsuki Yokoyama

Natsuki Yokoyama 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: 20020123216
    Abstract: A layer comprising a second metal silicide as a major constituent element or a layer comprising a second metal as a major constituent element is formed simultaneously by one single chemical vapor deposition process to the bottom surface of two out of there groups of openings etched in a dielectric film on a substrate. A surface comprising silicon as a major constituent element is exposed at each bottom (“through holes or local interconnection holes”) of the first group of openings, a surface comprising a first metal silicide as a major constituent element is exposed at each bottom of the second group of openings, and a surface comprising a first metal as a major constituent element is exposed at each bottom of the third group of openings. The manufacturing method provides low contact resistance and sufficiently small junction leakage current from a diffusion layer in connection with plugs or local interconnections, even if the etched area of the openings are of different depths, shapes, or sizes.
    Type: Application
    Filed: December 27, 2001
    Publication date: September 5, 2002
    Inventors: Natsuki Yokoyama, Masakazu Kawano
  • Publication number: 20020072180
    Abstract: There is provided a semiconductor device configured as follows. On a semiconductor substrate, a titanium oxide film which is an insulating film having a higher dielectric constant than that of a silicon dioxide film is formed as a gate insulating film, and a gate electrode is disposed thereon, resulting in a field effect transistor. The end portions in the gate length direction of the titanium oxide film are positioned inwardly from the respective end portions on the source side and on the drain side of the gate electrode, and the end portions of the titanium oxide film are positioned in a region in which the gate electrode overlaps with the source region and the drain region in plan configuration. This semiconductor device operates at a high speed, and is excellent in short channel characteristics and driving current. Further, in the semiconductor device, the amount of metallic elements introduced into a silicon substrate is small.
    Type: Application
    Filed: December 7, 2001
    Publication date: June 13, 2002
    Inventors: Jiro Yugami, Natsuki Yokoyama, Toshiyuki Mine, Yasushi Goto
  • Publication number: 20020055261
    Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, then insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.
    Type: Application
    Filed: November 30, 2001
    Publication date: May 9, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Akio Nishida, Kikuo Kusukawa, Toshiaki Yamanaka, Natsuki Yokoyama, Shinichiro Kimura, Norio Suzuki, Osamu Tsuchiya, Atsushi Ogishima
  • Patent number: 6380085
    Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, then insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: April 30, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Akio Nishida, Kikuo Kusukawa, Toshiaki Yamanaka, Natsuki Yokoyama, Shinichiro Kimura, Norio Suzuki, Osamu Tsuchiya, Atsushi Ogishima
  • Publication number: 20010053597
    Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, then insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.
    Type: Application
    Filed: December 29, 2000
    Publication date: December 20, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Akio Nishida, Kikuo Kusukawa, Toshiaki Yamanaka, Natsuki Yokoyama, Shinichiro Kimura, Norio Suzuki, Osamu Tsuchiya, Atsushi Ogishima
  • Patent number: 6204184
    Abstract: In a method of manufacturing a semiconductor device having a memory mat portion in which an active region and a field region are formed densely, after a polishing stopper film is deposited on a semiconductor substrate, there are formed grooves by etching a polishing stopper film of a field region and the semiconductor substrate. Then, after an insulating film is deposited so as to fill the grooves, the insulating film is partly removed from the memory mat portion by etching. Under this state, the insulating film is chemically mechanically polished until the polishing stopper film is exposed. The film thickness of the polishing stopper film on the active region can be reduced, and an electrical element isolation characteristic of the field region can be improved.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: March 20, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Akio Nishida, Kikuo Kusukawa, Toshiaki Yamanaka, Natsuki Yokoyama, Shinichiro Kimura, Norio Suzuki, Osamu Tsuchiya, Atsushi Ogishima
  • Patent number: 6103566
    Abstract: A dynamic random access memory or the like, in which in order to prevent the breakdown voltage deterioration of a capacitive element when a TiN film of an electrode material is deposited by the CVD method over a tantalum film constituting the capacitor insulating film of the capacitive element, a passivation film is formed in advance over the surface of the tantalum oxide film to prevent the tantalum oxide film from contacting a nitrogen-containing reducing gas, when the TiN film is deposited over the tantalum oxide film by the CVD method using a titanium-containing source gas and the nitrogen-containing reducing gas.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: August 15, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tsuyoshi Tamaru, Shinpei Iijima, Natsuki Yokoyama, Masayuki Nakata
  • Patent number: 6099598
    Abstract: Disclosed is a fabricating system including a plurality of processing apparatuses connected to each other by means of an inter-apparatus transporter, wherein one group of semiconductor wafers are processed in processing apparatuses and other group of wafers are transported to specified processing apparatuses for a time interval from (To+T) to a time To; and another group of wafers are processed and the remaining group of wafers are transported for a time interval from (To+T) to (To+2T). Since processing apparatuses can receive at least one of works from the inter-apparatus transporter for a time interval T min, the distribution of works from the transporter to processing apparatuses is completed for the time interval T min. The transporter is emptied for each time interval T min, and works are unloaded to the emptied transporter, which makes easy the scheduling, control and management of the transporting of a plurality of works in the fabricating system.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: August 8, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Natsuki Yokoyama, Yoshifumi Kawamoto, Eiichi Murakami, Fumihiko Uchida, Kenichi Mizuishi, Yoshio Kawamura
  • Patent number: 5981399
    Abstract: A semiconductor device fabrication apparatus having multiple processing chambers for different processes, where a substrate is carried in and out in a sophisticated manner, with their different internal ambient conditions being retained, so that the substrate is free from contamination, thereby manufacturing high-quality semiconductor devices at high throughput. The apparatus includes a movable buffer chamber having a wafer carriage means within a transfer chamber which faces a process chamber, an evacuation means which evacuates of gas the buffer chamber, transfer chamber and process chamber independently, a gas feed means, and a control means.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: November 9, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Kawamura, Tatuharu Yamamoto, Shigeo Moriyama, Yoshifumi Kawamoto, Natsuki Yokoyama, Fumihiko Uchida, Minoru Hidaka, Miyako Matsui
  • Patent number: 5858863
    Abstract: Disclosed is a fabricating system including a plurality of processing apparatuses connected to each other by means of an inter-apparatus transporter, wherein one group of semiconductor wafers are processed in processing apparatuses and other group of wafers are transported to specified processing apparatuses for a time interval from (To+T) to a time To; and another group of wafers are processed and the remaining group of wafers are transported for a time interval from (To+T) to (To+2T). Since processing apparatuses can receive at least one of works from the inter-apparatus transporter for a time interval T min, the distribution of works from the transporter to processing apparatuses is completed for the time interval T min. The transporter is emptied for each time interval T min, and works are unloaded to the emptied transporter, which makes easy the scheduling, control and management of the transporting of a plurality of works in the fabricating system.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: January 12, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Natsuki Yokoyama, Yoshifumi Kawamoto, Eiichi Murakami, Fumihiko Uchida, Kenichi Mizuishi, Yoshio Kawamura
  • Patent number: 5820679
    Abstract: Disclosed is a fabricating system including a plurality of processing apparatuses connected to each other by means of an inter-apparatus transporter, wherein one group of semiconductor wafers are processed in processing apparatuses and other group of wafers are transported to specified processing apparatuses for a time interval from (To+T) to a time To; and another group of wafers are processed and the remaining group of wafers are transported for a time interval from (To+T) to (To+2T). Since processing apparatuses can receive at least one of works from the inter-apparatus transporter for a time interval T min, the distribution of works from the transporter to processing apparatuses is completed for the time interval T min. The transporter is emptied for each time interval T min, and works are unloaded to the emptied transporter, which makes easy the scheduling, control and management of the transporting of a plurality of works in the fabricating system.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: October 13, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Natsuki Yokoyama, Yoshifumi Kawamoto, Eiichi Murakami, Fumihiko Uchida, Kenichi Mizuishi, Yoshio Kawamura
  • Patent number: 5601686
    Abstract: A wafer transport method including the steps of preparing a semiconductor process equipment having a transport chamber, a process chamber, an interface means for connecting the transport chamber to the process chamber, and a transport means for transporting a semiconductor wafer from the transport chamber to the process chamber by way of the interface means; inserting the transport means mounting a substrate in a communicating corridor including a supply means and an exhaust means; and transporting the substrate while performing the supply and exhaust by sequentially controlling a supply shutoff means, an exhaust shutoff means, and a communicating shutoff means according to the position of a conductance part formed of a gap between the transport means and the communicating corridor.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: February 11, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Kawamura, Yoshifumi Kawamoto, Fumihiko Uchida, Kenichi Mizuishi, Natsuki Yokoyama, Eiichi Murakami, Yoshinori Nakayama, Eiichi Seya
  • Patent number: 5562800
    Abstract: A wafer transport method includes the steps of preparing a semiconductor process equipment having a transport chamber and a process chamber. An interface means connects the transport chamber to the process chamber. A transport means transports a semiconductor wafer from the transport chamber to the process chamber by way of the interface means. The transport means mounting a substrate is inserted into a communicating corridor including a supply means and an exhaust means. The substrate is transported while performing the supply and exhaust by sequentially controlling a supply shutoff means, an exhaust shutoff means, and a communicating shutoff means according to the position of a conductance part formed of a gap between the transport means and the communicating corridor.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: October 8, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Kawamura, Yoshifumi Kawamoto, Fumihiko Uchida, Kenichi Mizuishi, Natsuki Yokoyama, Eiichi Murakami, Yoshinori Nakayama, Eiichi Seya
  • Patent number: 5270232
    Abstract: A very thin oxide film is formed at an opening formed in an insulator film and a conductor layer, on a substrate, and impurity-containing polysilicon is formed on the sidewall of the opening. Impurity diffusion from the from the silicon into the substrate through the very thin oxide film causes a lowering in effective concentration of the diffused impurities, resulting in the formation of shallower source/drain region. Thereafter, a gate insulator film and a gate electrode are formed on the substrate surface in an area bounded by an insulator film formed on the sidewall of the opening. The gate electrode smaller than the opening, the size of which corresponds to the limit of processing, and the shallower source/drain region afford a miniaturized MOSFET.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: December 14, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Shinichiro Kimura, Shoji Shukuri, Hiromasa Noda, Digh Hisamoto, Hideyuki Matsuoka, Kazuyoshi Torii, Natsuki Yokoyama, Toshiyuki Yoshimura, Kazunori Tsujimoto, Eiji Takeda
  • Patent number: 5270259
    Abstract: A silicone resin is applied on a substrate to form a coating film. The coating film is subjected to a reactive ion etching in an atmosphere containing at least O.sub.2. Thus, the film is inorganized in its surface and has a distribution of the residue, an organic radical, contained therein gradually increasing in the depth thereof. This permits an insulating film having excellent heat endurance to be formed without generation of any cracks. This insulating film is very useful as an interlayer insulating film for multi-layer wiring.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: December 14, 1993
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Shinichi Ito, Yoshio Homma, Eiji Sasaki, Natsuki Yokoyama
  • Patent number: 5177589
    Abstract: In forming a metal or metal silicide film by CVD, a fluoro-silane is used as a reaction gas, or a fluoro-silane is added to a source gas. Examples of the metal halide used in the present invention include fluorides and chlorides of tungsten, molybdenum, titanium, tantalum and niobium. Among them, fluorides of tungsten and molybdenum are more desirable particularly from the viewpoint of the availability of the deposited metal or metal silicide. It is preferred that the source gases, i.e. silane series gas and metal halide, be diluted with a carrier gas such as nitrogen, hydrogen, helium or argon, and this is also true of the fluoro-silane. The total pressure is preferably 0.01 to 10 Torr. The reaction temperature is desirably 200.degree. to 800.degree. C., more desirably 300.degree. to 500.degree. C. Plasma CVD instead of thermal CVD may be employed for the purpose of lowering the reaction temperature.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: January 5, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Nobuyoshi Kobayashi, Hidekazu Goto, Masayuki Suzuki, Yoshio Homma, Natsuki Yokoyama, Yoshitaka Nakamura
  • Patent number: 5175017
    Abstract: In forming a metal or metal silicide film by CVD, a fluorosilane is used as a reaction gas, or a fluoro-silane is added to a source gas. Examples of the metal halide used in the present invention include fluorides and chlorides of tungsten, molybdenum, titanium, tantalum and niobium. Among them, fluorides of tungsten and molybdenum are more desirable particularly from the viewpoint of the availability of the deposited metal or metal silicide. It is preferred that the source gases, i.e. silane series gas and metal halide, be diluted with a carrier gas such as nitrogen, hydrogen, helium or argon, and this is also true of the fluoro-silane. The total pressure is preferably 0.01 to 10 Torr. The reaction temperature is desirably 200.degree. to 800.degree. C., more desirably 300.degree. to 500.degree. C. Plasma CVD instead of thermal CVD may be employed for the purpose of lowering the reaction temperature.
    Type: Grant
    Filed: January 28, 1991
    Date of Patent: December 29, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Nobuyoshi Kobayashi, Hidekazu Goto, Masayuki Suzuki, Yoshio Homma, Natsuki Yokoyama
  • Patent number: 4897709
    Abstract: A semiconductor device includes a titanium nitride film as a barrier which is formed in a hole. The width or diameter of the hole is smaller than 1 .mu.m, and the aspect ratio thereof is larger than 0.7. The sidewall of the hole is substantially perpendicular to the surface of a semiconductor substrate. By the low pressure CVD method with a cold wall type CVD apparatus, it becomes possible to form the titanium nitride film having excellent characteristics with a good step coverage in a considerably fine hole having a large aspect ratio.
    Type: Grant
    Filed: May 26, 1988
    Date of Patent: January 30, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Natsuki Yokoyama, Yoshio Homma, Kenji Hinode, Kiichiro Mukai
  • Patent number: 4792842
    Abstract: Disclosed is a semiconductor device and method for manufacturing the same, which is provided with a first wiring layer whose thickness within a contact hole is great in a lower portion of the contact hole and is small in an upper portion thereof. Since the first wiring layer at the lower portion of the contact hole is sufficiently thick, reaction between a second wiring layer formed on the first wiring layer and a substrate is effectively prevented. The first wiring layer is formed by bias sputtering in which a bias voltage is applied to the substrate.
    Type: Grant
    Filed: November 24, 1987
    Date of Patent: December 20, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Honma, Sukeyoshi Tsunekawa, Natsuki Yokoyama, Hiroshi Morisaki