Patents by Inventor Yasuhiro Iguchi

Yasuhiro Iguchi 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: 20140197373
    Abstract: A light-receiving device includes a light-receiving layer having an undoped multi-quantum well structure; a cap layer disposed on the light-receiving layer, the cap layer including a semiconductor layer doped with a p-type impurity; a mesa structure including the cap layer; a p-type region extending from the p-type semiconductor layer toward the light-receiving layer, the p-type region including the p-type impurity diffused from the semiconductor layer in the mesa structure; a p-n junction formed at an end of the p-type region; and an electrode disposed on the cap layer of the mesa structure. The mesa structure is defined by a trench surrounding the mesa. The trench has a bottom that reaches the vicinity of an upper surface of the light-receiving layer. The p-n junction is located in the light-receiving layer or at the boundary between the light-receiving layer and the cap layer disposed on the light-receiving layer.
    Type: Application
    Filed: January 14, 2014
    Publication date: July 17, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yasuhiro IGUCHI, Youichi NAGAI
  • Publication number: 20140175585
    Abstract: A method for manufacturing a light-receiving device includes the steps of forming a stacked semiconductor layer including a non-doped light-receiving layer, the light-receiving layer having an n-type conductivity; forming a selective growth mask made of an insulating film on the stacked semiconductor layer, the selective growth mask having a pattern including a plurality of openings; selectively growing a selective growth layer doped with a p-type impurity on a portion of the stacked semiconductor layer using the selective growth mask; and forming a p-n junction in a region of the light-receiving layer by diffusing the p-type impurity doped in the selective growth layer into the light-receiving layer during growing the selective growth layer. Each of the regions including the p-n junctions corresponds to one of the selective growth layers. The p-n junction in one of the regions is formed separately from the p-n junctions in the other regions.
    Type: Application
    Filed: December 20, 2013
    Publication date: June 26, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Yasuhiro IGUCHI
  • Patent number: 8729527
    Abstract: A light-receiving element includes a group III-V compound semiconductor stacked structure that includes an absorption layer having a pn-junction therein. The stacked structure is formed on a group III-V compound semiconductor substrate. The absorption layer has a multiquantum well structure composed of group III-V compound semiconductors, and the pn-junction is formed by selectively diffusing an impurity element into the absorption layer. A diffusion concentration distribution control layer composed of a III-V group semiconductor is disposed in contact with the absorption layer on a side of the absorption layer opposite the side adjacent to the group III-V compound semiconductor substrate. The bandgap energy of the diffusion concentration distribution control layer is smaller than that of the group III-V compound semiconductor substrate. The concentration of the impurity element selectively diffused in the diffusion concentration distribution control layer is 5×1016/cm3 or less toward the absorption layer.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: May 20, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Kohei Miura, Hiroshi Inada, Youichi Nagai
  • Patent number: 8642943
    Abstract: A light-receiving element includes an InP substrate 1, a light-receiving layer 3 having an MQW and located on the InP substrate 1, a contact layer 5 located on the light-receiving layer 3, a p-type region 6 extending from a surface of the contact layer 5 to the light-receiving layer, and a p-side electrode 11 that forms an ohmic contact with the p-type region. The light-receiving element is characterized in that the MQW has a laminated structure including pairs of an InxGa1-xAs (0.38?x?0.68) layer and a GaAs1-ySby (0.25?y?0.73) layer, and in the GaAs1-ySby layer, the Sb content y in a portion on the InP substrate side is larger than the Sb content y in a portion on the opposite side.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: February 4, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hiroki Mori, Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai, Kouhei Miura, Hideaki Nakahata, Katsushi Akita, Takashi Ishizuka, Kei Fujii
  • Publication number: 20130334492
    Abstract: A light-receiving element includes a III-V group compound semiconductor substrate, a light-receiving layer having a type II multi-quantum well structure disposed on the substrate, and a type I wavelength region reduction means for reducing light in a wavelength region of type I absorption in the type II multi-quantum well structure disposed on a light incident surface or between the light incident surface and the light-receiving layer.
    Type: Application
    Filed: March 14, 2013
    Publication date: December 19, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Hiroshi Inada
  • Publication number: 20130313521
    Abstract: An object of the present invention is to provide, for example, a photodiode that can have sufficiently high sensitivity in a near-infrared wavelength range of 1.5 ?m to 1.8 ?m and can have a low dark current. A photodiode (10) according to the present invention includes a buffer layer (2) positioned on and in contact with an InP substrate (1), and an absorption layer (3) positioned on and in contact with the buffer layer, wherein the absorption layer includes 50 or more pairs in which a first semiconductor layer 3a and a second semiconductor layer 3b constitute a single pair, the first semiconductor layer 3a having a bandgap energy of 0.73 eV or less, the second semiconductor layer 3b having a larger bandgap energy than the first semiconductor layer 3a, and the first semiconductor layer 3a and the second semiconductor layer 3b constitute a strain-compensated quantum well structure and each have a thickness of 1 nm or more and 10 nm or less.
    Type: Application
    Filed: February 3, 2012
    Publication date: November 28, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Katsushi Akita, Takashi Ishizuka, Kei Fujii, Youichi Nagai, Hiroshi Inada, Yasuhiro Iguchi
  • Publication number: 20130292646
    Abstract: A light receiving device includes a microlens 21 located in each of regions corresponding to pixels, the microlens being disposed on a rear surface of an InP substrate 1. The microlens is formed by using a resin material having a range of a transmittance of light in the wavelength region between 0.7 and 3 ?m of 25% or less, the transmittance being 70% or more.
    Type: Application
    Filed: January 7, 2012
    Publication date: November 7, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Tadashi Saitoh, Yasushi Fujimura, Kazunori Tanaka
  • Patent number: 8564666
    Abstract: An image pickup device, a visibility support apparatus, a night vision device, a navigation support apparatus, and a monitoring device are provided in which noise and dark current are suppressed to thereby provide clear images regardless of whether it is day or night. The device includes a light-receiving layer 3 having a multi-quantum well structure and a diffusion concentration distribution control layer 4 disposed on the light-receiving layer so as to be opposite an InP substrate 1, wherein the light-receiving layer has a band gap wavelength of 1.65 to 3 ?m, the diffusion concentration distribution control layer has a lower band gap energy than InP, a pn junction is formed for each light-receiving element by selective diffusion of an impurity element, and the impurity selectively diffused in the light-receiving layer has a concentration of 5×1016/cm3 or less.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: October 22, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Youichi Nagai, Yasuhiro Iguchi
  • Patent number: 8546758
    Abstract: A food quality examination device using a high-sensitivity light-receiving element. The light-receiving element includes a III-V compound semiconductor stacked structure including an absorption layer having a pn-junction therein, wherein the absorption layer has a multiquanturn well structure composed of group III-V compound semiconductors, the pn-junction is formed by selectively diffusing an impurity element into the absorption layer, a diffusion concentration distribution control layer composed of III-V group semiconductor is disposed in contact with the absorption layer on a side of the absorption layer opposite the side adjacent to the group III-V compound semiconductor substrate, the bandgap energy of the diffusion concentration distribution control layer is smaller than that of the group III-V semiconductor substrate, the concentration of the impurity element selectively diffused in the diffusion concentration distribution control layer is decreased to be 5×1016/cm3 or less toward the absorption layer.
    Type: Grant
    Filed: July 24, 2009
    Date of Patent: October 1, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Youichi Nagai, Yasuhiro Iguchi
  • Publication number: 20130248821
    Abstract: A light receiving element includes an InP substrate that is transparent to light having a wavelength of 3 to 12 ?m, a buffer layer located in contact with the InP substrate, and a light-receiving layer having a multiple quantum well structure, the light-receiving layer having a cutoff wavelength of 3 ?m or more and being lattice-matched with the buffer layer. In the light receiving element, the buffer layer is epitaxially grown on the InP substrate while the buffer layer and the InP substrate exceed a range of a normal lattice-matching condition, and the buffer layer is constituted by a GaSb layer.
    Type: Application
    Filed: November 29, 2011
    Publication date: September 26, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kohei Miura, Hiroshi Inada, Yasuhiro Iguchi, Tadashi Saito
  • Patent number: 8513759
    Abstract: A photodiode array for near infrared rays that includes photodiodes having a uniform size and a uniform shape, has high selectivity for the wavelength of received light between the photodiodes, and has high sensitivity with the aid of a high-quality semiconducting crystal containing a large amount of nitrogen, a method for manufacturing the photodiode array, and an optical measurement system are provided. The steps of forming a mask layer 2 having a plurality of openings on a first-conductive-type or semi-insulating semiconductor substrate 1, the openings being arranged in one dimension or two dimensions, and selectively growing a plurality of semiconductor layers 3a, 3b, and 3c including an absorption layer 3b in the openings are included.
    Type: Grant
    Filed: October 18, 2010
    Date of Patent: August 20, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai
  • Publication number: 20130099203
    Abstract: A photodetector and a method of manufacturing the photodetector are provided, in which variation in sensitivity is suppressed over the near-infrared region from the short wavelength side including 1.3 ?m to the long wavelength side. The photodetector includes, on an InP substrate, an absorption layer of a type II multiple quantum well structure comprising a repeated structure of a GaAsSb layer and an InGaAs layer, and has sensitivity in the near-infrared region including wavelengths of 1.3 ?m and 2.0 ?m. The ratio of the sensitivity at the wavelength of 1.3 ?m to the sensitivity at the wavelength of 2.0 ?m is not smaller than 0.5 but not larger than 1.6.
    Type: Application
    Filed: June 15, 2011
    Publication date: April 25, 2013
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Katsushi Akita, Takashi Ishizuka, Kei Fujii, Hideaki Nakahata, Youichi Nagai, Hiroshi Inada, Yasuhiro Iguchi
  • Publication number: 20130048838
    Abstract: A light-receiving element includes an InP substrate 1, a light-receiving layer 3 having an MQW and located on the InP substrate 1, a contact layer 5 located on the light-receiving layer 3, a p-type region 6 extending from a surface of the contact layer 5 to the light-receiving layer, and a p-side electrode 11 that forms an ohmic contact with the p-type region. The light-receiving element is characterized in that the MQW has a laminated structure including pairs of an InxGa1-xAs (0.38?x?0.68) layer and a GaAs1-ySby (0.25?y?0.73) layer, and in the GaAs1-ySby layer, the Sb content y in a portion on the InP substrate side is larger than the Sb content y in a portion on the opposite side.
    Type: Application
    Filed: December 3, 2010
    Publication date: February 28, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Hiroki Mori, Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai, Kouhei Miura, Hideaki Nakahata, Katsushi Akita, Takashi Ishizuka, Kei Fujii
  • Patent number: 8373156
    Abstract: Provided is a biological component detection device with which a biological component can be detected at high sensitivity by using an InP-based photodiode in which a dark current is reduced without using a cooling mechanism and the sensitivity is extended to a wavelength of 1.8 ?m or more. An absorption layer 3 has a multiple quantum well structure composed of group III-V semiconductors, a pn-junction 15 is formed by selectively diffusing an impurity element in the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016/cm3 or less, the diffusion concentration distribution control layer has an n-type impurity concentration of 2×1015/cm3 or less before the diffusion, the diffusion concentration distribution control layer having a portion adjacent to the absorption layer, the portion having a low impurity concentration.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: February 12, 2013
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Youichi Nagai, Yasuhiro Iguchi
  • Publication number: 20130032780
    Abstract: A photodiode and the like capable of preventing the responsivity on the short wavelength side from deteriorating while totally improving the responsivity in a type II MQW structure, is provided. The photodiode is formed on a group III-V compound semiconductor substrate 1, and includes a pixel P. The photodiode includes an absorption layer 3 of a type II MQW structure, which is located on the substrate 1. The MQW structure includes fifty or more pairs of two different types of group III-V compound semiconductor layers 3a and 3b. The thickness of one of the two different types of group III-V compound semiconductor layers, which layer 3a has a higher potential of a valence band, is thinner than the thickness of the other layer 3b.
    Type: Application
    Filed: September 28, 2011
    Publication date: February 7, 2013
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Kei Fujii, Takashi Ishizuka, Katsushi Akita, Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai
  • Publication number: 20120298957
    Abstract: The present invention provides a light receiving element array etc., having a high light-reception sensitivity in the near-infrared region, an optical sensor device, and a method for producing the light receiving element array. A light receiving element array 55 includes an n-type buffer layer 2 disposed on an InP substrate 1, an absorption layer 3 having a type-II MQW, a contact layer 5 disposed on the absorption layer, and a p-type region extending to the n-type buffer layer 2 through the absorption layer 3, wherein the p-type region formed by selective diffusion is separated from the p-type region of an adjacent light receiving element by a region that is not subjected to selective diffusion, and, in the n-type buffer layer, a p-n junction 15 is formed on a crossed face of a p-type carrier concentration of the p-type region and an n-type carrier concentration of the buffer layer.
    Type: Application
    Filed: March 10, 2011
    Publication date: November 29, 2012
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Hiroshi Inada, Youichi Nagai, Hideaki Nakahata, Katsushi Akita, Takashi Ishizuka, Kei Fujii
  • Publication number: 20120274771
    Abstract: An image pickup device, a visibility support apparatus, a night vision device, a navigation support apparatus, and a monitoring device are provided in which noise and dark current are suppressed to thereby provide clear images regardless of whether it is day or night. The device includes a light-receiving layer 3 having a multi-quantum well structure and a diffusion concentration distribution control layer 4 disposed on the light-receiving layer so as to be opposite an InP substrate 1, wherein the light-receiving layer has a band gap wavelength of 1.65 to 3 ?m, the diffusion concentration distribution control layer has a lower band gap energy than InP, a pn junction is formed for each light-receiving element by selective diffusion of an impurity element, and the impurity selectively diffused in the light-receiving layer has a concentration of 5×1016/cm3 or less.
    Type: Application
    Filed: July 13, 2012
    Publication date: November 1, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Youichi Nagai, Yasuhiro Iguchi
  • Patent number: 8274127
    Abstract: A photodiode array includes a substrate of a common read-out control circuit; and a plurality of photodiodes arrayed on the substrate and each including an absorption layer, and a pair of a first conductive-side electrode and a second conductive-side electrode. In this photodiode array, each of the photodiodes is isolated from adjacent photodiodes, the first conductive-side electrodes are provided on first conductivity-type regions and electrically connected in common across all the photodiodes, and the second conductive-side electrodes are provided on second conductivity-type regions and individually electrically connected to read-out electrodes of the read-out control circuit.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: September 25, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Youichi Nagai, Yasuhiro Iguchi
  • Publication number: 20120223290
    Abstract: A light-receiving element includes a group III-V compound semiconductor stacked structure that includes an absorption layer having a pn-junction therein. The stacked structure is formed on a group III-V compound semiconductor substrate. The absorption layer has a multi- quantum well structure composed of group III-V compound semiconductors, and the pn-junction is formed by selectively diffusing an impurity element into the absorption layer. A diffusion concentration distribution control layer composed of a III-V group semiconductor is disposed in contact with the absorption layer on a side of the absorption layer opposite the side adjacent to the group III-V compound semiconductor substrate. The bandgap energy of the diffusion concentration distribution control layer is smaller than that of the group III-V compound semiconductor substrate. The concentration of the impurity element selectively diffused in the diffusion concentration distribution control layer is 5×1016/cm3 or less toward the absorption layer.
    Type: Application
    Filed: April 19, 2012
    Publication date: September 6, 2012
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yasuhiro Iguchi, Kohei Miura, Hiroshi Inada, Youichi Nagai
  • Patent number: 8258061
    Abstract: A circumferential portion of an epitaxial wafer is removed to remove an anomalously grown elevated portion formed in a circumferential chamfer. An epitaxial layer in the circumferential portion is removed with a width q=t to 5t wherein t is the thickness of the epitaxial layer so that the surface of a substrate is exposed. Therefore, cracking of the epitaxial layer in processing steps can be prevented.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: September 4, 2012
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuhiro Iguchi, Nobuyuki Mitsui