Patents by Inventor Toshiaki SAKATA
Toshiaki SAKATA 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).
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Patent number: 11939667Abstract: A method for manufacturing a wavelength conversion member, includes: providing a wavelength conversion layer having a phosphor-containing portion and a light reflecting portion surrounding the phosphor-containing portion, and the wavelength conversion layer having an upper surface, a bottom surface and at least one side surface; forming a light-blocking film on the upper surface of the wavelength conversion layer; and removing a part of the light-blocking film by laser processing to expose at least a part of the phosphor-containing portion from the light-blocking film.Type: GrantFiled: April 14, 2021Date of Patent: March 26, 2024Assignee: NICHIA CORPORATIONInventors: Naoki Eboshi, Hiroaki Yuto, Hiroki Sakata, Toshiaki Yamashita, Akinori Hara
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Patent number: 11430862Abstract: A semiconductor device has an active region through which current flows and a termination structure region. On a front surface of a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type is provided. On a surface of the first semiconductor layer in the active region, a first parallel pn structure is provided including first columns of the first conductivity type and second columns of a second conductivity type disposed repeatedly alternating one another in a plane parallel to the front surface. In the termination structure region, a second parallel pn structure is provided including third columns of the first conductivity type and fourth columns of the second conductivity type disposed repeatedly alternating one another. On a surface of the second parallel pn structure, a first semiconductor region of the second conductivity type is provided including plural regions apart from one another.Type: GrantFiled: March 2, 2020Date of Patent: August 30, 2022Assignee: FUJI ELECTRIC CO., LTD.Inventor: Toshiaki Sakata
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Publication number: 20200328273Abstract: A semiconductor device has an active region through which current flows and a termination structure region. On a front surface of a semiconductor substrate of a first conductivity type, a first semiconductor layer of the first conductivity type is provided. On a surface of the first semiconductor layer in the active region, a first parallel pn structure is provided including first columns of the first conductivity type and second columns of a second conductivity type disposed repeatedly alternating one another in a plane parallel to the front surface. In the termination structure region, a second parallel pn structure is provided including third columns of the first conductivity type and fourth columns of the second conductivity type disposed repeatedly alternating one another. On a surface of the second parallel pn structure, a first semiconductor region of the second conductivity type is provided including plural regions apart from one another.Type: ApplicationFiled: March 2, 2020Publication date: October 15, 2020Applicant: FUJI ELECTRIC CO., LTD.Inventor: Toshiaki SAKATA
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Patent number: 10692751Abstract: In each n-type epitaxial layer, p-type impurity regions are respectively formed by performing for each stacking of an n-type epitaxial layer, ion implantation using a resist mask. In a first n-type epitaxial layer, a p-type impurity region is formed at an inner wall of an impurity diffusion trench formed by dry etching. In a second and third n-type epitaxial layer, p-type impurity regions are formed respectively at an inner wall of impurity diffusion trenches that are recesses respectively corresponding to the impurity diffusion trenches of the first and the second n-type epitaxial layers respectively therebelow. The resist mask has an opening width that is wider than widths of open ends of the impurity diffusion trenches. The p-type impurity regions are connected by thermal diffusion processing, thereby forming a parallel pn layer constituted by p-type regions having a high aspect ratio and n-type regions respectively between the p-type regions.Type: GrantFiled: March 27, 2019Date of Patent: June 23, 2020Assignee: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki Sakata, Takeyoshi Nishimura, Isamu Sugai, Kazuya Yamaguchi
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Publication number: 20190348318Abstract: In each n-type epitaxial layer, p-type impurity regions are respectively formed by performing for each stacking of an n-type epitaxial layer, ion implantation using a resist mask. In a first n-type epitaxial layer, a p-type impurity region is formed at an inner wall of an impurity diffusion trench formed by dry etching. In a second and third n-type epitaxial layer, p-type impurity regions are formed respectively at an inner wall of impurity diffusion trenches that are recesses respectively corresponding to the impurity diffusion trenches of the first and the second n-type epitaxial layers respectively therebelow. The resist mask has an opening width that is wider than widths of open ends of the impurity diffusion trenches. The p-type impurity regions are connected by thermal diffusion processing, thereby forming a parallel pn layer constituted by p-type regions having a high aspect ratio and n-type regions respectively between the p-type regions.Type: ApplicationFiled: March 27, 2019Publication date: November 14, 2019Applicant: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki SAKATA, Takeyoshi NISHIMURA, Isamu SUGAI, Kazuya YAMAGUCHI
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Patent number: 10276654Abstract: A semiconductor device including a substrate, an active portion and a well region both formed in the substrate on a first surface side thereof, and a low-resistivity layer formed in the substrate on a second surface side thereof. A first parallel pn structure is formed in the substrate between the active portion and the low-resistivity layer, the first parallel pn structure having a first region and a second region that are repeatedly alternated at a first repetition pitch. A second parallel pn structure is formed in the substrate between the well region and the low-resistivity layer, the second parallel pn structure having a third region and a fourth region that are repeatedly alternated at a second repetition pitch that is smaller than the first repetition pitch, the well region and the second parallel pn structure being isolated from each other.Type: GrantFiled: June 27, 2016Date of Patent: April 30, 2019Assignee: FUJI ELECTRIC CO., LTD.Inventor: Toshiaki Sakata
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Patent number: 10211286Abstract: A first parallel pn layer having a first n-type region and a first p-type region junctioned alternately and repeatedly is disposed in an element active portion. The first parallel pn layer has a striped planar layout. A second parallel pn layer having a second n-type region and a second p-type region junctioned alternately and repeatedly is disposed in a high voltage structure. The second parallel pn layer has a striped planar layout in a direction identical to that of the first parallel pn layer. An intermediate region having a third parallel pn layer and a fourth parallel pn layer of a lower impurity quantity than the first parallel pn layer is disposed between the first and second parallel pn layers, and formed by diffusing impurity implanting regions becoming the first and the second parallel pn layers formed separated from each other to a region in which no impurity is ion-implanted.Type: GrantFiled: December 20, 2017Date of Patent: February 19, 2019Assignee: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki Sakata, Yasushi Niimura, Shunji Takenoiri
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Patent number: 10199458Abstract: Provided is a semiconductor device having a superjunction structure formed by a first conduction type column and a second conduction type column, including a first region of the superjunction structure in which a PN ratio increases in a direction from a first surface side to a second surface side of the superjunction structure; and a second region of the superjunction structure that contacts the first region and is adjacent to a channel region of the semiconductor device, wherein a PN ratio of the second region is less than the PN ratio at an end of the first region on the second surface side and thickness of the second region is less than thickness of the first region.Type: GrantFiled: December 3, 2015Date of Patent: February 5, 2019Assignee: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki Sakata, Mutsumi Kitamura
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Patent number: 10090408Abstract: A SJ-MOSFET includes a parallel pn layer in which an n-type drift region and a p-type partition region are alternately arranged repeatedly along a direction parallel to a base main-surface. The n-type drift region and the p-type partition region have total impurity amounts that are roughly the same and widths that are basically constant over an entire depth direction. The n-type drift region is configured to have an n-type impurity concentration profile in which an impurity concentration of a portion on the drain-side is higher than an impurity concentration of a portion on the source-side by ?Cnx. The p-type partition region is configured to have a p-type impurity concentration profile in which an impurity concentration of a portion on the drain-side is higher than an impurity concentration of a portion on the source-side by ?Cph, and an impurity concentration of part of the portion on the source-side is relatively low.Type: GrantFiled: August 1, 2017Date of Patent: October 2, 2018Assignee: FUJI ELECTRIC CO., LTD.Inventors: Ryo Maeta, Toshiaki Sakata, Shunji Takenoiri
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Patent number: 10008562Abstract: A first parallel pn layer in which first n-type regions and first p-type regions are disposed in a plan view layout of stripes in an element active portion. A second parallel pn layer has a plan view layout of stripes oriented in the same direction as that of the stripes of the first parallel pn layer in a breakdown voltage structure portion. Corner portions of the first parallel pn layer has a plan view shape where stepped regions formed by shortening the length of the first n-type and p-type regions in steps are disposed in a stepwise arrangement. The stepped regions continue with a second parallel pn layer via an intermediate region lower in average impurity concentration than the first parallel pn layer.Type: GrantFiled: January 15, 2018Date of Patent: June 26, 2018Assignee: FUJI ELECTRIC CO., LTD.Inventors: Yasushi Niimura, Toshiaki Sakata, Shunji Takenoiri
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Publication number: 20180158899Abstract: A first parallel pn layer in which first n-type regions and first p-type regions are disposed in a plan view layout of stripes in an element active portion. A second parallel pn layer has a plan view layout of stripes oriented in the same direction as that of the stripes of the first parallel pn layer in a breakdown voltage structure portion. Corner portions of the first parallel pn layer has a plan view shape where stepped regions formed by shortening the length of the first n-type and p-type regions in steps are disposed in a stepwise arrangement. The stepped regions continue with a second parallel pn layer via an intermediate region lower in average impurity concentration than the first parallel pn layer.Type: ApplicationFiled: January 15, 2018Publication date: June 7, 2018Applicant: FUJI ELECTRIC CO., LTD.Inventors: Yasushi Niimura, Toshiaki Sakata, Shunji Takenoiri
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Publication number: 20180114832Abstract: A first parallel pn layer having a first n-type region and a first p-type region junctioned alternately and repeatedly is disposed in an element active portion. The first parallel pn layer has a striped planar layout. A second parallel pn layer having a second n-type region and a second p-type region junctioned alternately and repeatedly is disposed in a high voltage structure. The second parallel pn layer has a striped planar layout in a direction identical to that of the first parallel pn layer. An intermediate region having a third parallel pn layer and a fourth parallel pn layer of a lower impurity quantity than the first parallel pn layer is disposed between the first and second parallel pn layers, and formed by diffusing impurity implanting regions becoming the first and the second parallel pn layers formed separated from each other to a region in which no impurity is ion-implanted.Type: ApplicationFiled: December 20, 2017Publication date: April 26, 2018Applicant: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki SAKATA, Yasushi NIIMURA, Shunji TAKENOIRI
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Publication number: 20180076315Abstract: A SJ-MOSFET includes a parallel pn layer in which an n-type drift region and a p-type partition region are alternately arranged repeatedly along a direction parallel to a base main-surface. The n-type drift region and the p-type partition region have total impurity amounts that are roughly the same and widths that are basically constant over an entire depth direction. The n-type drift region is configured to have an n-type impurity concentration profile in which an impurity concentration of a portion on the drain-side is higher than an impurity concentration of a portion on the source-side by ?Cnx. The p-type partition region is configured to have a p-type impurity concentration profile in which an impurity concentration of a portion on the drain-side is higher than an impurity concentration of a portion on the source-side by ?Cph, and an impurity concentration of part of the portion on the source-side is relatively low.Type: ApplicationFiled: August 1, 2017Publication date: March 15, 2018Applicant: FUJI ELECTRIC CO., LTD.Inventors: Ryo MAETA, Toshiaki SAKATA, Shunji TAKENOIRI
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Patent number: 9887260Abstract: A first parallel pn layer in which first n-type regions and first p-type regions are disposed in a plan view layout of stripes in an element active portion. A second parallel pn layer has a plan view layout of stripes oriented in the same direction as that of the stripes of the first parallel pn layer in a breakdown voltage structure portion. Corner portions of the first parallel pn layer has a plan view shape where stepped regions formed by shortening the length of the first n-type and p-type regions in steps are disposed in a stepwise arrangement. The stepped regions continue with a second parallel pn layer via an intermediate region lower in average impurity concentration than the first parallel pn layer.Type: GrantFiled: March 11, 2016Date of Patent: February 6, 2018Assignee: FUJI ELECTRIC CO., LTD.Inventors: Yasushi Niimura, Toshiaki Sakata, Shunji Takenoiri
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Patent number: 9881997Abstract: A first parallel pn layer having a first n-type region and a first p-type region junctioned alternately and repeatedly is disposed in an element active portion. The first parallel pn layer has a striped planar layout. A second parallel pn layer having a second n-type region and a second p-type region junctioned alternately and repeatedly is disposed in a high voltage structure. The second parallel pn layer has a striped planar layout in a direction identical to that of the first parallel pn layer. An intermediate region having a third parallel pn layer and a fourth parallel pn layer of a lower impurity quantity than the first parallel pn layer is disposed between the first and second parallel pn layers, and formed by diffusing impurity implanting regions becoming the first and the second parallel pn layers formed separated from each other to a region in which no impurity is ion-implanted.Type: GrantFiled: March 3, 2016Date of Patent: January 30, 2018Assignee: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki Sakata, Yasushi Niimura, Shunji Takenoiri
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Patent number: 9653595Abstract: An n? drift layer is a parallel pn layer having an n-type region and a p-type region are alternately arranged in the direction parallel to the main surface so as to come into contact with each other, and have a width in a direction parallel to the main surface of the substrate which is less than a length in a direction perpendicular to the main surface of the substrate. A second-main-surface-side lower end portion of the p-type region has a structure in which a high-concentration lower end portion and a low-concentration lower end portion of a p-type low-concentration region are repeated at a predetermined pitch in the direction parallel to the main surface of the substrate. It is possible to provide a super junction MOS semiconductor device which can improve a trade-off relationship between turn-off loss and turn-off dv/dt and improve avalanche resistance.Type: GrantFiled: September 10, 2014Date of Patent: May 16, 2017Assignee: FUJI ELECTRIC CO., LTD.Inventors: Yasushi Niimura, Toshiaki Sakata
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Publication number: 20160308037Abstract: A semiconductor device including a substrate, an active portion and a well region both formed in the substrate on a first surface side thereof, and a low-resistivity layer formed in the substrate on a second surface side thereof. A first parallel pn structure is formed in the substrate between the active portion and the low-resistivity layer, the first parallel pn structure having a first region and a second region that are repeatedly alternated at a first repetition pitch. A second parallel pn structure is formed in the substrate between the well region and the low-resistivity layer, the second parallel pn structure having a third region and a fourth region that are repeatedly alternated at a second repetition pitch that is smaller than the first repetition pitch, the well region and the second parallel pn structure being isolated from each other.Type: ApplicationFiled: June 27, 2016Publication date: October 20, 2016Applicant: FUJI ELECTRIC CO., LTD.Inventor: Toshiaki SAKATA
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Publication number: 20160293693Abstract: A first parallel pn layer in which first n-type regions and first p-type regions are disposed in a plan view layout of stripes in an element active portion. A second parallel pn layer has a plan view layout of stripes oriented in the same direction as that of the stripes of the first parallel pn layer in a breakdown voltage structure portion. Corner portions of the first parallel pn layer has a plan view shape where stepped regions formed by shortening the length of the first n-type and p-type regions in steps are disposed in a stepwise arrangement. The stepped regions continue with a second parallel pn layer via an intermediate region lower in average impurity concentration than the first parallel pn layer.Type: ApplicationFiled: March 11, 2016Publication date: October 6, 2016Applicant: FUJI ELECTRIC CO., LTD.Inventors: Yasushi NIIMURA, Toshiaki SAKATA, Shunji TAKENOIRI
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Publication number: 20160293692Abstract: A first parallel pn layer having a first n-type region and a first p-type region junctioned alternately and repeatedly is disposed in an element active portion. The first parallel pn layer has a striped planar layout. A second parallel pn layer having a second n-type region and a second p-type region junctioned alternately and repeatedly is disposed in a high voltage structure. The second parallel pn layer has a striped planar layout in a direction identical to that of the first parallel pn layer. An intermediate region having a third parallel pn layer and a fourth parallel pn layer of a lower impurity quantity than the first parallel pn layer is disposed between the first and second parallel pn layers, and formed by diffusing impurity implanting regions becoming the first and the second parallel pn layers formed separated from each other to a region in which no impurity is ion-implanted.Type: ApplicationFiled: March 3, 2016Publication date: October 6, 2016Applicant: FUJI ELECTRIC CO., LTD.Inventors: Toshiaki SAKATA, Yasushi NIIMURA, Shunji TAKENOIRI
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Publication number: 20160225847Abstract: Provided is a semiconductor device having a superjunction structure formed by a first conduction type column and a second conduction type column, including a first region of the superjunction structure in which a PN ratio increases in a direction from a first surface side to a second surface side of the superjunction structure; and a second region of the superjunction structure that contacts the first region and is adjacent to a channel region of the semiconductor device, wherein a PN ratio of the second region is less than the PN ratio at an end of the first region on the second surface side and thickness of the second region is less than thickness of the first region.Type: ApplicationFiled: December 3, 2015Publication date: August 4, 2016Inventors: Toshiaki SAKATA, Mutsumi KITAMURA