Fujitsu Corporation

Norikazu Nakamura

Junji Kotani

Tetsuro Ishiguro

Atsushi Yamada

Keiji Watanabe

Hiroshi Chiba

Masayuki Takeda

Shirou Ozaki

Tsukasa Itani

Kenji Imanishi

Yukiko Oshikubo

Yoshiharu Kasamatsu

Eishin Yamakawa

Toyoo Miyajima

Takayuki Musashi

Kazuaki Kurihara

Toshihide Kikkawa

Toshihiro Ohki

Masahito Kanamura

Shoichi Miyahara

Shoichi Suda

Kozo Makiyama

Jun Watanabe

Tadahiro Imada

Junichi Kon

Takashi Toyoguchi

Hisao Shigematsu

Takeshi Toukairin

Shinichi Nakayama

A compound semiconductor device includes a first compound semiconductor layer containing a p-type impurity, a second compound semiconductor layer disposed over the first compound semiconductor layer and containing InGaN, an electron transit layer disposed over the second compound semiconductor layer, and an electron supply layer disposed over the electron transit layer.

Compound semiconductor device with high power and reduced off-leakage and method for manufacturing the same

Disclosed is a compound semiconductor device that includes an electron transit layer; an electron supply layer disposed above the electron transit layer, and including a first region and a second region, the second region having a composition higher in Al than the first region and covering the first region from at least a bottom part of the second region; a first electrode disposed above the first region; and a second electrode disposed above the second region.

Compound semiconductor device and fabrication method

A compound semiconductor device includes a substrate, a compound semiconductor layer formed over the substrate, a channel layer formed over the compound semiconductor layer, an electron supply layer formed over the channel layer, and a source electrode, a drain electrode, and a gate electrode that are formed apart from each other over the electron supply layer. A quantum well structure is formed by the compound semiconductor layer, the channel layer, and the electron supply layer.

Compound semiconductor device with quantum well structure, power supply device, and high-frequency amplifier

A compound semiconductor device includes an electron transit layer, a spacer layer disposed on the electron transit layer, and an electron supply layer disposed on the spacer layer and containing a donor impurity. The electron supply layer has a concentration distribution of the donor impurity where the donor impurity is at a first concentration at an interface between the electron supply layer and the spacer layer and at a second concentration lower than the first concentration at an upper surface of the electron supply layer, and a concentration of the donor impurity at one of arbitrarily-selected two positions closer to the upper surface in a thickness direction of the electron supply layer is less than the concentration of the donor impurity at another one of the two positions closer to the interface in the thickness direction.

Compound semiconductor device and method for manufacturing the same

A compound semiconductor device includes: a carrier transit layer; a carrier supply layer that is formed over the carrier transit layer and is made of InAlN; and a spacer layer that is formed between the carrier transit layer and the carrier supply layer and is made of at least one of AlGaN and InAlGaN.

Compound semiconductor device and manufacturing method thereof

A semiconductor crystal substrate includes a first buffer layer formed of a nitride semiconductor over a substrate, a second buffer layer formed of a nitride semiconductor on the first buffer layer, a first semiconductor layer formed of a nitride semiconductor on or over the second buffer layer, and a second semiconductor layer formed of a nitride semiconductor on the first semiconductor layer. The Fe concentration of the first buffer layer is higher than the C concentration of the first buffer layer. The C concentration of the second buffer layer is higher than the Fe concentration of the second buffer layer.

Semiconductor crystal substrate with Fe doping

A compound semiconductor device includes: a first layer of nitride semiconductor, the first layer being doped with Fe; a channel layer of nitride semiconductor above the first layer; and a barrier layer of nitride semiconductor above the channel layer, wherein the channel layer includes: a two-dimensional electron gas region in which the two-dimensional electron gas exists; and an Al-containing region between the two-dimensional electron gas region and the first layer, an Al concentration in the Al-containing region being 5&#xd7;10atoms/cmor more and less than 1&#xd7;10atoms/cm.

Compound semiconductor device and method of manufacturing the same

A disclosed semiconductor device includes a buffer layer formed of a compound semiconductor on a substrate, a first semiconductor layer formed of a compound semiconductor on the buffer layer, a second semiconductor layer formed of a compound semiconductor on the first semiconductor layer, a gate electrode, a source electrode, and a drain electrode formed on the second semiconductor layer, and a heat dissipation part formed below the gate electrode. In the semiconductor device, all or part of the second semiconductor layer and the first semiconductor layer is present between the gate electrode and the heat dissipation part, the heat dissipation part includes a heat dissipation layer and a first intermediate layer formed between the heat dissipation layer and both of the buffer layer and first semiconductor layer, and the heat dissipation layer is formed of a material containing carbon.

Semiconductor device and method of fabricating the semiconductor device

A semiconductor crystal substrate includes a substrate, a first semiconductor layer including a nitride semiconductor and formed over the substrate, a second semiconductor layer including a nitride semiconductor and formed over the first semiconductor layer, a first cap layer formed on the second semiconductor layer, and a second cap layer formed on the first cap layer. Each of the first semiconductor layer and the second semiconductor layer has a single-crystal structure, the first cap layer has one of a single-crystal structure and a polycrystalline structure, and the second cap layer has an amorphous structure.

Semiconductor device and method therefor including multiple cap layers with amorphous layer

A compound semiconductor device includes: a GaN-based channel layer; a barrier layer of nitride semiconductor above the channel layer; and a cap layer of nitride semiconductor above the barrier layer, wherein the cap layer includes: a first region doped with Fe; and a second region above the first region, a concentration of Fe in the second region being lower than a concentration of Fe in the first region.

Gallium nitride based high electron mobility transistor (GaN-HEMT) device with an iron-doped cap layer and method of manufacturing the same

A film deposition apparatus includes: a plasma generating section configured to generate plasma between a cathode target and an anode; a film deposition chamber in which a base material is placed; and a magnetic-field filter section configured to remove a particle from the plasma by a magnetic field and to transfer the plasma to the film deposition chamber. The magnetic-field filter section includes: a first housing area to which a first voltage is applied; and a second housing area, provided downstream of the first housing area in the moving direction of the plasma, to which a second voltage is applied.

Film deposition method

A compound semiconductor device includes: a compound semiconductor multilayer structure including a first buffer layer composed of AlN; and a second buffer layer composed of AlGaN and formed above the first buffer layer, wherein the second buffer layer contains carbon, and wherein the concentration of carbon in the second buffer layer increases with increasing distance from a lower surface of the second buffer layer toward an upper surface of the second buffer layer.

Compound semiconductor device, method for producing the same, power-supply unit, and high-frequency amplifier

A compound semiconductor device includes a compound semiconductor stacked structure, the compound semiconductor stacked structure including: an electron transit layer; an electron supply layer formed above the electron transit layer, the electron supply layer containing an n-type impurity; and a cap layer formed above the electron supply layer and containing the n-type impurity, in which in the electron supply layer, a concentration of the n-type impurity contained therein is non-uniform in a film thickness direction and a concentration of the n-type impurity in a surface of the cap layer side is lower than a maximum concentration of the n-type impurity in the electron supply layer.

A semiconductor device includes a first semiconductor layer formed over a substrate, a second semiconductor layer formed over the first semiconductor layer, a source electrode and a drain electrode formed over the second semiconductor layer, an insulating film formed over the second semiconductor layer, a gate electrode formed over the insulating film, and a protection film covering the insulating film, the protection film being formed by thermal CVD, thermal ALD, or vacuum vapor deposition.

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Sagamihara, Japan

Norikazu Nakamura