Patents by Inventor Makoto Kitabatake

Makoto Kitabatake 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: 20090309215
    Abstract: A semiconductor module (10) includes a heat sink (1), an electronic component (2), a semiconductor device (3), and a thermally-conductive sheet member (4). The thermally-conductive sheet member (4) covers a part of the semiconductor device (3) and has a lower part (4b) and a side part (4c). The lower part (4b) is in contact with a mounting face (11a) of the heat sink (1). The side part (4c) extends from the lower part (4b) and covers a first side surface (3c) of the semiconductor device (3). The electronic component (2) is disposed across the side part (4c) of the thermally-conductive sheet member (4) from the semiconductor device (3).
    Type: Application
    Filed: September 13, 2007
    Publication date: December 17, 2009
    Inventor: Makoto Kitabatake
  • Publication number: 20090225578
    Abstract: The present invention provides a semiconductor device and an electric apparatus each of which can realize both high-speed switching operation and energy loss reduction and excels in resistance to current concentration based on a counter electromotive voltage generated by, for example, an inductance load of the electric apparatus.
    Type: Application
    Filed: July 7, 2006
    Publication date: September 10, 2009
    Inventor: Makoto Kitabatake
  • Publication number: 20090104762
    Abstract: Ion implantation is carried out to form a p-well region and a source region in parts of a high resistance SiC layer on a SiC substrate, and a carbon film is deposited over the substrate. With the carbon film deposited over the substrate, annealing for activating the implanted dopant ions is performed, and then the carbon film is removed. Thus, a smooth surface having hardly any surface roughness caused by the annealing is obtained. Furthermore, if a channel layer is epitaxially grown, the surface roughness of the channel layer is smaller than that of the underlying layer. Since the channel layer having a smooth surface is provided, it is possible to obtain a MISFET with a high current drive capability.
    Type: Application
    Filed: December 18, 2008
    Publication date: April 23, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Osamu KUSUMOTO, Makoto KITABATAKE, Masao UCHIDA, Kunimasa TAKAHASHI, Kenya YAMASHITA, Masahiro HAGIO, Kazuyuki SAWADA
  • Patent number: 7521786
    Abstract: At least two switching devices each including a substrate formed of a wide bandgap semiconductor, source and gate electrodes formed in a principal surface side of the substrate, and a drain electrode formed on the back surface of the substrate are stacked so that respective upper surface sides of the switching face each other.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: April 21, 2009
    Assignee: Panasonic Corporation
    Inventors: Makoto Kitabatake, Kazuhiko Asada, Hidekazu Yamashita, Nobuyoshi Nagagata, Kazuhiro Nobori, Hideki Omori, Masanori Ogawa
  • Patent number: 7507999
    Abstract: An accumulation-mode MISFET comprises: a high-resistance SiC layer 102 epitaxially grown on a SiC substrate 101; a well region 103; an accumulation channel layer 104 having a multiple ?-doped layer formed on the surface region of the well region 103; a contact region 105; a gate insulating film 108; and a gate electrode 110. The accumulation channel layer 104 has a structure in which undoped layers 104b and ?-doped layers 104a allowing spreading movement of carriers to the undoped layers 104b under a quantum effect are alternately stacked. A source electrode 111 is provided which enters into the accumulation channel layer 104 and the contact region 105 to come into direct contact with the contact region 105. It becomes unnecessary that a source region is formed by ion implantation, leading to reduction in fabrication cost.
    Type: Grant
    Filed: July 9, 2003
    Date of Patent: March 24, 2009
    Assignee: Panasonic Corporation
    Inventors: Osamu Kusumoto, Makoto Kitabatake, Kunimasa Takahashi, Kenya Yamashita, Ryoko Miyanaga, Masao Uchida
  • Patent number: 7473929
    Abstract: Ion implantation is carried out to form a p-well region and a source region in parts of a high resistance SiC layer on a SiC substrate, and a carbon film is deposited over the substrate. With the carbon film deposited over the substrate, annealing for activating the implanted dopant ions is performed, and then the carbon film is removed. Thus, a smooth surface having hardly any surface roughness caused by the annealing is obtained. Furthermore, if a channel layer is epitaxially grown, the surface roughness of the channel layer is smaller than that of the underlying layer. Since the channel layer having a smooth surface is provided, it is possible to obtain a MISFET with a high current drive capability.
    Type: Grant
    Filed: July 1, 2004
    Date of Patent: January 6, 2009
    Assignee: Panasonic Corporation
    Inventors: Osamu Kusumoto, Makoto Kitabatake, Masao Uchida, Kunimasa Takahashi, Kenya Yamashita, Masahiro Hagio, Kazuyuki Sawada
  • Patent number: 7462540
    Abstract: A method for fabricating a semiconductor device includes the steps of implanting ions into a silicon carbide thin film (2) formed on a silicon carbide substrate (1), heating the silicon carbide substrate in a reduced pressure atmosphere to form a carbon layer (5) on the surface of the silicon carbide substrate, and performing activation annealing with respect to the silicon carbide substrate in an atmosphere under a pressure higher than in the step of forming the carbon layer (5) and at a temperature higher than in the step of forming the carbon layer (5).
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: December 9, 2008
    Assignee: Panasonic Corporation
    Inventors: Kunimasa Takahashi, Makoto Kitabatake, Kenya Yamashita, Masao Uchida, Osamu Kusumoto, Ryoko Miyanaga
  • Publication number: 20080265260
    Abstract: A power device having a transistor structure is formed by using a wide band gap semiconductor. A current path 20 of the power device includes: a JFET (junction) region 2, a drift region 3, and a substrate 4, which have ON resistances exhibiting a positive temperature dependence; and a channel region 1, which has an ON resistance exhibiting a negative temperature dependence. A temperature-induced change in the ON resistance of the entire power device is derived by allowing a temperature-induced change ?Rp in the ON resistance in the JFET (junction) region 2, the drift region 3, and the substrate 4, which have ON resistances exhibiting a positive temperature dependence, and a temperature-induced change ?Rn in the ON resistance in the channel region 1, which has an ON resistance exhibiting a negative temperature dependence, to cancel out each other. With respect to an ON resistance of the entire power device at ?30° C.
    Type: Application
    Filed: June 10, 2005
    Publication date: October 30, 2008
    Inventors: Makoto Kitabatake, Osamu Kusumoto, Masao Uchida, Kunimasa Takahashi, Kenya Yamashita, Koichi Hashimoto
  • Patent number: 7436031
    Abstract: A semiconductor device according to this invention includes: two level shift switches (28A and 28B) each having first and second electrodes, a control electrode, a signal output electrode, and a first semiconductor region forming a transistor device section (28a,28b) which intervenes between the first electrode and the signal output electrode and is brought into or out of conduction according to a signal inputted to the control electrode and a resistor device section (Ra,Rb) which intervenes between the signal output electrode and the second electrode, the first semiconductor region comprising a wide bandgap semiconductor; and a diode (23) having a cathode-side electrode, an anode-side electrode, and a second semiconductor region comprising a wide bandgap semiconductor.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: October 14, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Makoto Kitabatake, Osamu Kusumoto, Masao Uchida, Kunimasa Takahashi, Kenya Yamashita, Ryoko Miyanaga, Koichi Hashimoto
  • Patent number: 7381993
    Abstract: In a semiconductor device of the present invention, the top surface of an n-type silicon carbide layer formed on a silicon carbide substrate is miscut from the (0001) plane in the <11-20> direction. A gate electrode, a source electrode and other elements are arranged such that in a channel region, the dominating current flows along a miscut direction. In the present invention, a gate insulating film is formed and then heat treatment is performed in an atmosphere containing a group-V element. In this way, the interface state density at the interface between the silicon carbide layer and the gate insulating film is reduced. As a result, the electron mobility becomes higher in a miscut direction A than in the direction perpendicular to the miscut direction A.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: June 3, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masao Uchida, Makoto Kitabatake, Osamu Kusumoto, Kenya Yamashita, Kunimasa Takahashi, Ryoko Miyanaga
  • Publication number: 20070176230
    Abstract: In a semiconductor device of the present invention, the top surface of an n-type silicon carbide layer formed on a silicon carbide substrate is miscut from the (0001) plane in the <11-20> direction. A gate electrode, a source electrode and other elements are arranged such that in a channel region, the dominating current flows along a miscut direction. In the present invention, a gate insulating film is formed and then heat treatment is performed in an atmosphere containing a group-V element. In this way, the interface state density at the interface between the silicon carbide layer and the gate insulating film is reduced. As a result, the electron mobility becomes higher in a miscut direction A than in the direction perpendicular to the miscut direction A.
    Type: Application
    Filed: April 3, 2007
    Publication date: August 2, 2007
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Masao Uchida, Makoto Kitabatake, Osamu Kusumoto, Kenya Yamashita, Kunimasa Takahashi, Ryoko Miyanaga
  • Publication number: 20070158778
    Abstract: A semiconductor device according to this invention includes: two level shift switches (28A and 28B) each having first and second electrodes, a control electrode, a signal output electrode, and a first semiconductor region forming a transistor device section (28a,28b) which intervenes between the first electrode and the signal output electrode and is brought into or out of conduction according to a signal inputted to the control electrode and a resistor device section (Ra,Rb) which intervenes between the signal output electrode and the second electrode, the first semiconductor region comprising a wide bandgap semiconductor; and a diode (23) having a cathode-side electrode, an anode-side electrode, and a second semiconductor region comprising a wide bandgap semiconductor.
    Type: Application
    Filed: August 26, 2005
    Publication date: July 12, 2007
    Inventors: Makoto Kitabatake, Osamu Kusumoto, Masao Uchida, Kunimasa Takahashi, Kenya Yamashita, Ryoko Miyanaga, Koichi Hashimoto
  • Patent number: 7230273
    Abstract: A semiconductor module comprises independently operable segments 1 (semiconductor elements) on a SiC substrate. Each segment 1 comprises a source electrode pad 2 and a gate electrode pad 3 both provided to the principal surface side of the SiC substrate, and a drain electrode pad provided on the back surface side of the SiC substrate. The semiconductor module further comprises an isolation region such as a trench or a Schottky diode for electrically isolating the adjacent segments 1 from each other. Only electrode pads 2 and 3 of each of the segments 1 determined as conforming items by a test are connected to electrode terminals 41 and 43, respectively.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: June 12, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Makoto Kitabatake, Osamu Kusumoto, Masao Uchida, Kunimasa Takahashi, Kenya Yamashita
  • Patent number: 7217954
    Abstract: An inventive semiconductor device is provided with: a silicon carbide substrate 1; an n-type high resistance layer 2; well regions 3 provided in a surface region of the high resistance layer 2; a p+ contact region 4 provided within each well region 3; a source region 5 provided to laterally surround the p+ contact region 4 within each well region 3; first source electrodes 8 provided on the source regions 5 and made of nickel; second source electrodes 9 that cover the first source electrodes 8 and that are made of aluminum; a gate insulating film 6 provided on a portion of the high resistance layer 2 sandwiched between the two well regions 3; a gate electrode 10 made of aluminum; and an interlayer dielectric film 11 that covers the second source electrodes 9 and the gate electrode 10 and that is made of silicon oxide.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: May 15, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Osamu Kusumoto, Makoto Kitabatake, Kunimasa Takahashi, Kenya Yamashita, Ryoko Miyanaga, Masao Uchida
  • Patent number: 7214984
    Abstract: In a semiconductor device of the present invention, the top surface of an n-type silicon carbide layer formed on a silicon carbide substrate is miscut from the (0001) plane in the <11-20> direction. A gate electrode, a source electrode and other elements are arranged such that in a channel region, the dominating current flows along a miscut direction. In the present invention, a gate insulating film is formed and then heat treatment is performed in an atmosphere containing a group-V element. In this way, the interface state density at the interface between the silicon carbide layer and the gate insulating film is reduced. As a result, the electron mobility becomes higher in a miscut direction A than in the direction perpendicular to the miscut direction A.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: May 8, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masao Uchida, Makoto Kitabatake, Osamu Kusumoto, Kenya Yamashita, Kunimasa Takahashi, Ryoko Miyanaga
  • Patent number: 7126169
    Abstract: The present invention provides a semiconductor element in which the field-effect transistor and the Schottky diode are arranged such that a depletion layer stemming from the Schottky diode is superimposed on a depletion layer stemming from a junction between a second conductivity type semiconductor constituting the field-effect transistor and a drift region (first conductivity type semiconductor) in an off-state. Furthermore, the present invention provides a semiconductor element in which the field-effect transistor and the Schottky diode are arranged so that a second conductivity type semiconductor other than the second conductivity type semiconductor constituting the field-effect transistor is not interposed between the electric field effect transistor and the Schottky diode. According to preferable embodiments of the present invention, the reverse recovery time due to a parasitic diode can be reduced by providing the Schottky diode such that the element area of the semiconductor element is not increased.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: October 24, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Makoto Kitabatake
  • Publication number: 20060220026
    Abstract: In a semiconductor device of the present invention, the top surface of an n-type silicon carbide layer formed on a silicon carbide substrate is miscut from the (0001) plane in the <11-20> direction. A gate electrode, a source electrode and other elements are arranged such that in a channel region, the dominating current flows along a miscut direction. In the present invention, a gate insulating film is formed and then heat treatment is performed in an atmosphere containing a group-V element. In this way, the interface state density at the interface between the silicon carbide layer and the gate insulating film is reduced. As a result, the electron mobility becomes higher in a miscut direction A than in the direction perpendicular to the miscut direction A.
    Type: Application
    Filed: November 24, 2004
    Publication date: October 5, 2006
    Inventors: Masao Uchida, Makoto Kitabatake, Osamu Kusumoto, Kenya Yamashita, Kunimasa Takahashi, Ryoko Miyanaga
  • Publication number: 20060220027
    Abstract: A method for fabricating a semiconductor device includes the steps of implanting ions into a silicon carbide thin film (2) formed on a silicon carbide substrate (1), heating the silicon carbide substrate in a reduced pressure atmosphere to form a carbon layer (5) on the surface of the silicon carbide substrate, and performing activation annealing with respect to the silicon carbide substrate in an atmosphere under a pressure higher than in the step of forming the carbon layer (5) and at a temperature higher than in the step of forming the carbon layer (5).
    Type: Application
    Filed: January 28, 2005
    Publication date: October 5, 2006
    Inventors: Kunimasa Takahashi, Makoto Kitabatake, Kenya Yamashita, Masao Uchida, Osamu Kusumoto, Ryoko Miyanaga
  • Publication number: 20060071246
    Abstract: At least two switching devices each including a substrate formed of a wide bandgap semiconductor, source and gate electrodes formed in a principal surface side of the substrate, and a drain electrode formed on the back surface of the substrate are stacked so that respective upper surface sides of the switching face each other.
    Type: Application
    Filed: December 6, 2005
    Publication date: April 6, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Makoto Kitabatake, Kazuhiko Asada, Hidekazu Yamashita, Nobuyoshi Nagagata, Kazuhiro Nobori, Hideki Omori, Masanori Ogawa
  • Publication number: 20060055027
    Abstract: A semiconductor apparatus includes a semiconductor chip 61 including a power semiconductor device using a wide band gap semiconductor, base materials 62 and 63, first and second intermediate members 65 and 68a, a heat conducting member 66, a radiation fin 67, and an encapsulating material 68 for encapsulating the semiconductor chip 61, the first and second intermediate member 65 and 68a and the heat conducting member 66. The tips of the base materials 62 and 63 work respectively as external connection terminals 62a and 63a. The second intermediate member 68a is made of a material with lower heat conductivity than the first intermediate member 65, and a contact area with the semiconductor chip 61 is larger in the second intermediate member 68a than in the first intermediate member.
    Type: Application
    Filed: September 6, 2004
    Publication date: March 16, 2006
    Inventors: Makoto Kitabatake, Osamu Kusumoto, Nasao Uchida, Kunimasa Takahashi, Kenya Yamashita