Patents by Inventor Yasushi Ogata
Yasushi Ogata 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: 6476791Abstract: In a peripheral driver circuit of a liquid crystal electro-optical device is comprised of a shift register circuit arranged by a plurality of registers, and a circuit for supplying power to each register. When an input signal is entered into an nth register, a supply of power to at least a portion of registers other than the nth register is stopped. The shift register circuit is constructed of a P-channel type TFT and a resistor. The circuit for supplying the power controls the supply of power to the shift register by using the output of the shift register circuit. This circuit for supplying the power is arranged by a P-channel type TFT and a resistor. The consumption power of the circuit for supplying the power is equal to and lower than that of the shift register circuit.Type: GrantFiled: August 27, 2001Date of Patent: November 5, 2002Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Jun Koyama, Yasushi Ogata, Shunpei Yamazaki
-
Patent number: 6465287Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystalline silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is performed in temperature above 750° C. after introducing elemental nickel to an amorphous silicon film 103 disposed on a quartz substrate 101. Then, after obtaining the crystalline silicon film 105, it is patterned to obtain a pattern 106. Then, another heat treatment is performed within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. A thermal oxide film 107 is formed in this step. At this time, the elemental nickel is gettered to the thermal oxide film 107. Next, the thermal oxide film 107 is removed. Thereby, a crystalline silicon film 106 having low concentration of the metal element and a high crystallinity can be obtained.Type: GrantFiled: January 16, 1997Date of Patent: October 15, 2002Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
-
Patent number: 6452211Abstract: A semiconductor thin film having extremely superior crystallinity and a semiconductor device using the semiconductor thin film having high performance are provided. The semiconductor thin film is manufactured in such a manner that after an amorphous semiconductor thin film is crystallized by using a catalytic element, a heat treatment is carried out in an atmosphere containing a halogen element to remove the catalytic element. The thus obtained crystalline semiconductor thin film has substantially {110} orientation. The concentration of C, N, and S remaining in the final semiconductor thin film is less than 5×1018 atoms/cm3, and the concentration of O is less than 1.5×1019 atoms/cm3.Type: GrantFiled: June 9, 1998Date of Patent: September 17, 2002Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisashi Ohtani, Shunpei Yamazaki, Jun Koyama, Yasushi Ogata, Akiharu Miyanaga
-
Publication number: 20020058362Abstract: An active matrix type display device having a sufficient auxiliary capacitance and a high aperture ratio is provided. In the device, an auxiliary capacitance (a black mask being in contact with an inorganic layer/the inorganic layer/a pixel electrode being in contact with the inorganic layer) is formed on an interlayer insulating film made of an organic resin film.Type: ApplicationFiled: May 29, 2001Publication date: May 16, 2002Inventors: Hisashi Ohtani, Yasushi Ogata
-
Publication number: 20020024497Abstract: In a peripheral driver circuit of a liquid crystal electro-optical device is comprised of a shift register circuit arranged by a plurality of registers, and a circuit for supplying power to each register. When an input signal is entered into an nth register, a supply of power to at least a portion of registers other than the nth register is stopped. The shift register circuit is constructed of a P-channel type TFT and a resistor. The circuit for supplying the power controls the supply of power to the shift register by using the output of the shift register circuit. This circuit for supplying the power is arranged by a P-channel type TFT and a resistor. The consumption power of the circuit for supplying the power is equal to and lower than that of the shift register circuit.Type: ApplicationFiled: August 27, 2001Publication date: February 28, 2002Inventors: Jun Koyama, Yasushi Ogata, Shunpei Yamazaki
-
Patent number: 6316810Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystal silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is implemented after introducing nickel element to an amorphous silicon film 103. Then, after obtaining the crystal silicon film, another heat treatment is implemented within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. At this time, HCl or the like is added to the atmosphere. A thermal oxide film 106 is formed in this step. At this time, gettering of the nickel element into the thermal oxide film 106 takes place. Next, the thermal oxide film 106 is removed. Thereby, a crystal silicon film 107 having low concentration of the metal element and a high crystalinity can be obtained.Type: GrantFiled: July 9, 1999Date of Patent: November 13, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
-
Patent number: 6307214Abstract: After an amorphous semiconductor thin film is crystallized by utilizing a catalyst element, the catalyst element is removed by performing a heat treatment in an atmosphere containing a halogen element. A resulting crystalline semiconductor thin film has features that it exhibits {110} orientation and that almost all crystal lattices have continuity at a crystal boundary. This type of grain boundaries greatly contribute to improving the carrier mobility, and make it possible to realize semiconductor devices having very high performance.Type: GrantFiled: May 27, 1998Date of Patent: October 23, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisashi Ohtani, Shunpei Yamazaki, Jun Koyama, Yasushi Ogata, Akiharu Miyanaga
-
Patent number: 6295047Abstract: In a peripheral driver circuit of a liquid crystal electro-optical device is comprised of a shift register circuit arranged by a plurality of registers, and a circuit for supplying power to each register. When an input signal is entered into an nth register, a supply of power to at least a portion of registers other than the nth register is stopped. The shift register circuit is constructed of a P-channel type TFT and a resistor. The circuit for supplying the power controls the supply of power to the shift register by using the output of the shift register circuit. This circuit for supplying the power is arranged by a P-channel type TFT and a resistor. The consumption power of the circuit for supplying the power is equal to and lower than that of the shift register circuit.Type: GrantFiled: April 28, 1999Date of Patent: September 25, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Jun Koyama, Yasushi Ogata, Shunpei Yamazaki
-
Patent number: 6271543Abstract: An active matrix type display device having a sufficient auxiliary capacitance and a high aperture ratio is provided. In the device, an auxiliary capacitance (a black mask being in contact with an inorganic layer/the inorganic layer/a pixel electrode being in contact with the inorganic layer) is formed on an interlayer insulating film made of an organic resin film.Type: GrantFiled: February 19, 1999Date of Patent: August 7, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisashi Ohtani, Yasushi Ogata
-
Publication number: 20010009783Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystal silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is implemented after introducing nickel to an amorphous silicon film. Then, after obtaining the crystal silicon film, another heat treatment is implemented within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. A thermal oxide film is formed in this step. At this time, gettering of the nickel element into the thermal oxide film takes place. Then, the thermal oxide film is removed. Thereby, a crystal silicon film having low concentration of the metal element and a high crystalinity can be obtained.Type: ApplicationFiled: February 21, 2001Publication date: July 26, 2001Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
-
Patent number: 6225966Abstract: In a reflection type liquid crystal panel, the flatness of a surface of a pixel electrode is secured. A drain electrode is extended to the lower portion of a reflecting pixel electrode. The drain electrode and an auxiliary capacitance electrode form an auxiliary capacitance. The drain electrode, a gate electrode, and a source wiring line exist, so that the roughness of the surface on which a resin layer is formed, is relaxed, and the securing of flatness by the resin layer is made easy. In this way, the reflecting pixel electrode can be formed on the flat surface.Type: GrantFiled: March 23, 1998Date of Patent: May 1, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisahi Ohtani, Yasushi Ogata, Takeshi Nishi, Yutaka Shionoiri
-
Patent number: 6225152Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystal silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is implemented after introducing nickel to an amorphous silicon film. Then, after obtaining the crystal silicon film, another heat treatment is implemented within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. A thermal oxide film is formed in this step. At this time, gettering of the nickel element into the thermal oxide film takes place. Then, the thermal oxide film is removed. Thereby, a crystal silicon film having low concentration of the metal element and a high crystalinity can be obtained.Type: GrantFiled: January 20, 1999Date of Patent: May 1, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
-
Patent number: 6180439Abstract: Concentration of metal element which promotes crystallization of silicon and which exists within a crystalline silicon film obtained by utilizing the metal element is reduced. A first heat treatment for crystallization is performed after introducing nickel to an amorphous silicon film 103. Then, laser light is irradiated to diffuse nickel element which is concentrated locally. After that, another heat treatment is performed within an oxidizing atmosphere at a temperature higher than that of the previous heat treatment. At this time, HCl or the like is added to the atmosphere. A thermal oxide film 106 is formed in this step. At this time, gettering of the nickel element into the thermal oxide film 106 takes place. Then, the thermal oxide film 106 is removed. Thereby, a crystalline silicon film 107 having low concentration of the metal element and a high crystallinity can be obtained.Type: GrantFiled: January 16, 1997Date of Patent: January 30, 2001Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame
-
Patent number: 6124602Abstract: In a semiconductor circuit using a silicon film in which crystals grow in the direction parallel to a substrate, the distance between the position of a starting region of crystal growth and the position of the respective active layers are made the same. Thus, the difference of the characteristics due to the difference of the distance of crystal growth is corrected.Type: GrantFiled: December 29, 1997Date of Patent: September 26, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisashi Ohtani, Jun Koyama, Yasushi Ogata, Shunpei Yamazaki
-
Patent number: 6124604Abstract: A wiring line to which a high-frequency signal is applied is electrically connected in parallel to an auxiliary wiring line via a plurality of contact holes. The contact holes are formed through an interlayer insulating film and arranged in vertical direction to the wiring line. Since the auxiliary wiring line is formed in the same layer as an electrode that constitutes a TFT, the electric resistance of the wiring line can be reduced effectively and waveform rounding of an applied high-frequency signal can be reduced without increasing the number of manufacturing steps.Type: GrantFiled: December 22, 1997Date of Patent: September 26, 2000Assignee: Semiconductor Energy Laboratory, Inc.Inventors: Jun Koyama, Hisashi Ohtani, Yasushi Ogata, Shunpei Yamazaki
-
Patent number: 6093934Abstract: Nickel is selectively held in contact with a particular region of an amorphous silicon film. Crystal growth parallel with a substrate is effected by performing a heat treatment. A thermal oxidation film is formed on the silicon film by performing a heat treatment in an oxidizing atmosphere containing a halogen element. During this step, in the silicon film, impurities included such as oxygen or chlorine, are segregated with extending along the crystal growth, the crystallinity is improved, and the gettering of nickel element proceeds. A thin-film transistor is formed so that the direction connecting source and drain regions coincides with the above crystal growth direction. As a result, a TFT having superior characteristics such as a mobility larger than 200 cm.sup.2 /Vs and an S value smaller than 100 mV/dec. can be obtained.Type: GrantFiled: January 17, 1997Date of Patent: July 25, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame, Hisashi Ohtani, Toshiji Hamatani
-
Patent number: 6088070Abstract: An conductive coating serves as a light shield film and is kept at a give voltage. A metal interconnection is located in the same layer as a source line and connected to the drain of a thin-film transistor. An interlayer insulating film is constituted of at least lower and upper insulating layers and formed between the conductive coating and the source line. According to one aspect of the invention, an auxiliary capacitor is formed by the metal interconnection and the conductive coating serving as both electrodes and at least the lower insulating layer film serving as a dielectric. The auxiliary capacitor is formed in a region of the interlayer insulating film in which the upper insulating layer has been removed by etching. According to another aspect of the invention, the conductive coating has a portion that is in contact with the lower insulating layer in a region where the conductive coating coextends with the metal interconnection.Type: GrantFiled: January 16, 1998Date of Patent: July 11, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Hisashi Ohtani, Yasushi Ogata, Yoshiharu Hirakata
-
Patent number: 6087679Abstract: After an amorphous semiconductor thin film is crystallized by utilizing a catalyst element, the catalyst element is removed by performing a heat treatment in an atmosphere containing a halogen element. A resulting crystalline semiconductor thin film exhibits {110} orientation. Since individual crystal grains have approximately equal orientation, the crystalline semiconductor thin film has substantially no grain boundaries and has such crystallinity as to be considered a single crystal or considered so substantially.Type: GrantFiled: July 22, 1998Date of Patent: July 11, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Hisashi Ohtani, Toru Mitsuki, Akiharu Miyanaga, Yasushi Ogata
-
Patent number: 6077731Abstract: A novel and very useful method for forming a crystal silicon film by introducing a metal element which promotes crystallization of silicon to an amorphous silicon film and for eliminating or reducing the metal element existing within the crystal silicon film thus obtained is provided. The method for fabricating a semiconductor device comprises steps of intentionally introducing the metal element which promotes crystallization of silicon to the amorphous silicon film and crystallizing the amorphous silicon film by a first heat treatment to obtain the crystal silicon film; eliminating or reducing the metal element existing within the crystal silicon film by implementing a second heat treatment within an oxidizing atmosphere; eliminating a thermal oxide film formed in the previous step; and forming another thermal oxide film on the surface of the region from which the thermal oxide film has been eliminated by implementing another thermal oxidation.Type: GrantFiled: January 17, 1997Date of Patent: June 20, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Satoshi Teramoto, Jun Koyama, Yasushi Ogata, Masahiko Hayakawa, Mitsuaki Osame, Hisashi Ohtani, Toshiji Hamatani
-
Patent number: 6013542Abstract: In a method of manufacturing a semiconductor device, a gate wiring and a source wiring of a thin film transistor in the course of manufacture are connected, and are finally divided, so that it is possible to prevent breakage of a gate insulating film due to influence of plasma at the formation of various insulating films or conductive films. Specifically, openings are formed at every formation of interlayer insulating films to first layer wirings to be finally divided, and dummy electrodes not serving as electrodes are formed in the openings. When patterning a final electrode, openings are further formed in the dummy electrodes, and the first layer wirings are divided through the openings.Type: GrantFiled: September 23, 1996Date of Patent: January 11, 2000Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventors: Shunpei Yamazaki, Jun Koyama, Yasushi Ogata, Satoshi Teramoto