Patents by Inventor Masahiko Doki

Masahiko Doki 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: 5976973
    Abstract: A method of manufacturing a semiconductor device has the steps of: forming a wiring pattern by dry etching a wiring layer on a semiconductor substrate, using a resist pattern as a mask; immersing the wiring pattern in amine containing liquid to remove deposition residues formed during the dry etching; then, processing the wiring pattern with fluid not containing amine and being capable of removing deposition residues; forming a conformal insulating layer on the processed wiring pattern; and forming an insulating layer having a planarizing function on the conformal insulating layer by CVD. This method is suitable for multi-layer wiring, and can form an interlayer insulating film having a satisfactory planarizing function.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: November 2, 1999
    Assignee: Fujitsu Ltd.
    Inventors: Koichiro Ohira, Katsuyuki Karakawa, Kazutoshi Izumi, Masahiko Doki
  • Patent number: 5763005
    Abstract: For a multilayer insulating film of a semiconductor device, the distributed quantity of carbon or fluorine is maximized at the interface between insulating films. The concentration of carbon present at the interface is 1.times.10.sup.20 atoms/cm.sup.3 or more.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: June 9, 1998
    Assignee: Fujitsu Limited
    Inventors: Yuji Furumura, Masahiko Doki, Hidetoshi Nishio
  • Patent number: 5620526
    Abstract: A cleaning of a plasma chamber is done by a NF.sub.3 plasma treatment (typically under 1 to 1.5 Torr). The etching rate of an oxide layer can be improved by inserting, between the NF.sub.3 plasma treatments, a low pressure (lower than 10.sup.-1 Torr) plasma treatment preferably in a plasma of oxygen, water vapor, silane, fluorine, a hydrate compound, nitrogen trifluoride, or a mixture of nitrogen trifluoride with at least one of hydrogen fluoride, fluorine, water vapor and hydride compounds.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: April 15, 1997
    Assignees: Fujitsu Limited, Fujitsu VLSI Limited
    Inventors: Hirofumi Watatani, Masahiko Doki, Shoji Okuda, Junya Nakahira, Hideaki Kikuchi
  • Patent number: 5506443
    Abstract: A multilayer insulating film of a semiconductor device, where the distributed quantity of carbon or fluorine is maximized at the interface between insulating films. The concentration of carbon present at the interface is 1.times.10.sup.20 atoms/cm.sup.3 or more.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: April 9, 1996
    Assignee: Fujitsu Limited
    Inventors: Yuji Furumura, Masahiko Doki, Hidetoshi Nishio
  • Patent number: 5310452
    Abstract: Provided is a plasma processing apparatus and method which has a plasma generating chamber into which gas is introduced and microwaves are transmitted, thereby generating plasma. The plasma is introduced into a processing chamber, in which a semiconductor substrate to be processed resides. An RF generator and DC generator are mixed together and are synchronized with the microwaves, such that they are applied to the substrate at the same times the microwaves act upon the gas to form plasma. Thus, variance of the DC bias and RF bias can be independently controlled, and damage to the substrate is reduced. In another embodiment, an RF bias voltage modulation circuit is used to shape the RF waveform in accordance with predetermined patterns.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: May 10, 1994
    Assignees: Fujitsu Limited, Fuji Electric Co., Ltd.
    Inventors: Masahiko Doki, Kiyoshi Ooiwa
  • Patent number: 5231057
    Abstract: A method for producing a semiconductor device includes the steps of forming a patterned wiring line on a first insulating layer, and depositing a second insulating layer on the patterned wiring line and the first insulating layer by a plasma-assisted CVD process in which a pulse-modulated plasma is generated and a gas containing hydrogen is used.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: July 27, 1993
    Assignee: Fujitsu Limited
    Inventors: Masahiko Doki, Junya Nakahira, Yuji Furumura
  • Patent number: 5183777
    Abstract: A method of forming a shallow junction comprises the step of: forming a film including a hydrogen compound with one element selected from the group of boron, phosphorus arsenic to a thickness of several atom layers to 1000 .ANG. on a silicon substrate and annealing the film, whereby an impurity region having a depth of 1000 .ANG. or less and an impurity concentration of 10.sup.18 to 10.sup.21 cm.sup.-3 is formed in the surface layer of the silicon layer.
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: February 2, 1993
    Assignee: Fujitsu Limited
    Inventors: Masahiko Doki, Michiko Takei
  • Patent number: 5160397
    Abstract: Provided is a plasma processing apparatus and method which has a plasma generating chamber into which gas is introduced and microwaves are transmitted, thereby generating plasma. The plasma is introduced into a processing chamber, in which a semiconductor substrate to be processed resides. An RF generator and DC generator are mixed together and are synchronized with the microwaves, such that they are applied to the substrate at the same times the microwaves act upon the gas to form plasma. Thus, variance of the DC bias and RF bias can be independently controlled, and damage to the substrate is reduced. In another embodiment, an RF bias voltage modulation circuit is used to shape the RF waveform in accordance with predetermined patterns.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: November 3, 1992
    Assignee: Fujitsu Limited and Fuji Electric Co., Ltd.
    Inventors: Masahiko Doki, Kiyoshi Ooiwa
  • Patent number: 5103285
    Abstract: A silicon carbide layer between a silicon substrate or layer and a metal layer because silicon carbide has many properties similar to those of silicon, has a very slow diffusion rate of a metal through the silicon carbide, or prevents a diffusion of a metal into the silicon, and can be deposited by CVD, which has an advantage of a good coverage over a step portion such as a contact window.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: April 7, 1992
    Assignee: Fujitsu Limited
    Inventors: Yuji Furumura, Fumitake Mieno, Takashi Eshita, Kikuo Itoh, Masahiko Doki
  • Patent number: 4891118
    Abstract: In a typical plasma processing apparatus, microwaves are generated into a processing chamber which contains a gas and a substrate. Magnetic fields transmitted into the processing chamber cause plasma to be produced when microwaves are generated. Typically an RF bias voltage is applied to the substrate during the process. By optimizing the RF bias voltage which the pulses of microwaves the apparatus produces a higher quality thin film, or etching process, without damaging the substrate surface.
    Type: Grant
    Filed: November 23, 1988
    Date of Patent: January 2, 1990
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Kiyoshi Ooiwa, Masahiko Doki