Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Chuo Kenkyusho

Hiroyuki Ueda

Masahiro Sugimoto

Tsutomu Uesugi

Tetsu Kachi

Masakazu Kanechika

Narumasa Soejima

Hidemoto Tomita

Tomohiko Mori

Yoshitaka Nakano

Takashi Okawa

Tetsuya Yamada

Hideo Hasegawa

Hiroyuki Mori

Atsushi Watanabe

Kazuyuki Nakanishi

Hideo Tachikawa

Yasushi Yamada

Tadashi Oshima

Yuichi Tanaka

Masayasu Ishiko

Yoshitaka Nagasato

Yukio Miyachi

Takatoshi Kato

Masahiro Kawakami

A semiconductor device includes a semiconductor substrate, a source electrode, a drain electrode, and a gate electrode disposed on the semiconductor substrate via a gate insulator film. The semiconductor substrate includes a first portion constituted of GaN and a second portion constituted of AlGaN (0&#x3c;x&#x2264;1). The first portion includes an n-type source region being in contact with the source electrode, an n-type drain region being in contact with the drain electrode, a p-type body region intervening between the source region and the drain region and being in contact with the source electrode, and an n-type drift region intervening between the body region and the drain region and having a carrier density that is lower than a carrier density of the drain region. The second portion includes a barrier region being in contact with each of the source electrode, the body region and the drift region.

Nitride semiconductor device

A switching element includes a semiconductor substrate that includes a first n-type semiconductor layer, a p-type body layer constituted by an epitaxial layer, and a second n-type semiconductor layer separated from the first n-type semiconductor layer by the body layer, a gate insulating film that covers a range across the surface of the first n-type semiconductor layer, the surface of the body layer, and the surface of the second n-type semiconductor layer, and a gate electrode that faces the body layer through the gate insulating film. An interface between the first n-type semiconductor layer and the body layer includes an inclined surface. The inclined surface is inclined such that the depth of the body layer increases as a distance from an end of the body layer increases in a horizontal direction. The inclined surface is disposed below the gate electrode.

Switching element having inclined body layer surfaces

A semiconductor device may include a nitride semiconductor layer, an insulation gate section, and a heterojunction region, wherein the nitride semiconductor layer may include an n-type vertical drift region, a p-type channel region adjoining the vertical drift region, and an n-type source region separated from the vertical drift region by the channel region, wherein the insulation gate section is opposed to a portion of the channel region that separates the vertical drift region and the source region, the heterojunction region is in contact with at least a part of a portion of the vertical drift region that is disposed at the one of main surfaces, and the heterojunction region is an n-type nitride semiconductor or an i-type nitride semiconductor having a bandgap wider than a bandgap of the vertical drift region.

Semiconductor device and manufacturing method of the same

A semiconductor device includes an outside-of-well n-type region, a p-type well region surrounded by the outside-of-well n-type region, an inside-of-well n-type region, and a gate electrode. The outside-of-well n-type region includes an impurity low-concentration region that is in contact with the p-type well region, and an impurity high-concentration region that is separated from the p-type well region by the impurity low-concentration region.

Semiconductor device

A method of manufacturing a switching element includes forming a recessed portion in a surface of a GaN semiconductor substrate in which a first n-type semiconductor layer is exposed on the surface, growing a p-type body layer within the recessed portion and on the surface of the GaN semiconductor substrate, removing a surface layer portion of the body layer to expose the first n-type semiconductor layer on the surface of the GaN semiconductor substrate, and leave the body layer within the recessed portion, forming a second n-type semiconductor layer which is separated from the first n-type semiconductor layer by the body layer and is exposed on the surface of the GaN semiconductor substrate, and forming a gate electrode which faces the body layer through an insulating film.

Method of manufacturing switching element having gallium nitride substrate

A semiconductor device is capable of accurately sensing a temperature of a semiconductor element incorporated in a semiconductor substrate. The semiconductor device includes a temperature sensor. The temperature sensor includes a first nitride semiconductor layer of p-type, a first sense electrode, and a second sense electrode. The first sense electrode and the second sense electrode are located to be capable of passing an electric current between the first sense electrode and the second sense electrode through the first nitride semiconductor layer.

Semiconductor device and manufacturing method for the same

A semiconductor device includes: an electron transit layer constituted of GaN; an electron supply layer constituted of InAlGaN (0&#x2266;x1&#x3c;1, 0&#x2266;y1&#x3c;1, 0&#x3c;1&#x2212;x1&#x2212;y1&#x3c;1) and provided on the electron transit layer; a source electrode and a drain electrode that are provided on the electron supply layer and located apart from each other; a threshold voltage adjustment layer constituted of InAlGaN (0&#x2266;x2&#x3c;1, 0&#x2266;y2&#x3c;1, 0&#x3c;1&#x2212;x2&#x2212;y2&#x2266;1) of a p-type and provided on a part of the electron supply layer located between the source electrode and the drain electrode; and a gate electrode provided on the threshold voltage adjustment layer. A high resistance layer is respectively interposed both between the gate electrode and the threshold voltage adjustment layer, and between the threshold voltage adjustment layer and the electron supply layer.

A semiconductor device has a stacked structure in which a p-GaN layer, an SI-GaN layer, and an AlGaN layer are stacked, and has a gate electrode that is formed at a top surface side of the AlGaN layer. A band gap of the AlGaN layer is wider than a band gap of the p-GaN layer and the SI-GaN layer. Moreover, impurity concentration of the SI-GaN layer is less than 1&#xd7;10cm. Semiconductor devices including III-V semiconductors may have a stable normally-off operation.

III-V HEMT devices

Both a HEMT and a SBD are formed on a nitride semiconductor substrate. The nitride semiconductor substrate comprises a HEMT gate structure region and an anode electrode region. A first laminated structure is formed at least in the HEMT gate structure region, and includes first to third nitride semiconductor layers. A second laminated structure is formed at least in a part of the anode electrode region, and includes first and second nitride semiconductor layers. The anode electrode contacts the front surface of the second nitride semiconductor layer. At least in a contact region in which the front surface of the second nitride semiconductor layer contacts the anode electrode, the front surface of the second nitride semiconductor layer is finished to be a surface by which the second nitride semiconductor layer forms a Schottky junction with the anode electrode.

Semiconductor device and method of manufacturing the same

A switching device provided herewith includes first to fourth semiconductor layers and a gate electrode. The second semiconductor layer is of a first conductive type or an un-dope type and located on the first semiconductor layer. A hetero junction is formed between the first and the second semiconductor layers. The third semiconductor layer is of a second conductive type and located on the second semiconductor layer. The fourth semiconductor layer is of a second conductive type and located on the third semiconductor layer. A hetero junction is formed between the third and the fourth semiconductor layers. The gate electrode electrically connected to the fourth semiconductor layer.

Switching device

A nitride semiconductor devicecomprises a nitride semiconductor layer. A gate insulating filmis formed on the surface of the nitride semiconductor layer. The gate insulating filmincludes a portion composed of an aluminum nitride filmand a portion composed of an insulating materialthat contains at least one of oxygen or silicon. A region Wof the nitride semiconductor layerfacing the aluminum nitride filmis included in a region Wof the nitride semiconductor layerfacing a gate electrode. The nitride semiconductor devicemay further comprise a nitride semiconductor lower layer. The nitride semiconductor layermay be stacked on the surface of the nitride semiconductor lower layer. The nitride semiconductor layermay have a larger band gap than that of the nitride semiconductor lower layerand have a heterojunction formed there between.

Nitride semiconductor device including gate insulating portion containing AIN

A semiconductor device is provided with a drain electrode, a semiconductor base plate, an electric current regulation layercovering a part of a surface of the semiconductor base plateand leaving a non-covered surfaceat the surface of the semiconductor base plate, a semiconductor layercovering a surface of the electric current regulation layer, and a source electrodeformed at a surface of the semiconductor layer. A drift region, a channel forming region, and a source regionare formed within the semiconductor layer. The drain electrodeis connected to a first terminal of a power source, and the source electrodeis connected to a second terminal of the power source. With this semiconductor layer, it is possible to increase withstand voltage or reduce the occurrence of current leakage.

Semiconductor device having vertical electrodes structure

A semiconductor devicecomprises a heterojunction between a lower semiconductor layermade of p-type gallium nitride and an upper semiconductor layermade of n-type AlGaN, wherein the upper semiconductor layerhas a larger band gap than the lower semiconductor layer. The semiconductor devicefurther comprises a drain electrodeformed on a portion of a top surface of the upper semiconductor layer, a source electrodeformed on a different portion of the top surface of the upper semiconductor layer, and a gate electrodeelectrically connected to the lower semiconductor layer. The semiconductor devicecan operate as normally-off.

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Nagakute, Japan

Hiroyuki Ueda