Fujitsu Corporation

Hitachi Cable Co., Ltd.

Sumitomo Chemical Company, Limited

Kenji Imanishi

Toshihide Kikkawa

Toyoo Miyajima

Takeshi Tanaka

Norikazu Nakamura

Masahito Kanamura

Yoshihiko Moriya

Yohei Otoki

Atsushi Yamada

Toshihiro Ohki

Keiji Watanabe

Shirou Ozaki

Masayuki Takeda

Hitoshi Tanaka

Tsuyoshi Takahashi

Tadahiro Imada

Tetsuro Ishiguro

Hisao Shigematsu

Sanae Shimizu

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.

Semiconductor device

An embodiment of a method of manufacturing a compound semiconductor device includes: forming an initial layer over a substrate; forming a buffer layer over the initial layer; forming an electron transport layer and an electron supply layer over the buffer layer; and forming a gate electrode, a source electrode and a gate electrode over the electron supply layer. The forming an initial layer includes: forming a first compound semiconductor film with a flow rate ratio being a first value, the flow rate ratio being a ratio of a flow rate of a V-group element source gas to a flow rate of a III-group element source gas; and forming a second compound semiconductor film with the flow rate ratio being a second value different from the first value over the first compound semiconductor film. The method further includes forming an Fe-doped region between the buffer layer and the electron transport layer.

Compound semiconductor device and method of manufacturing the same

A first AlGaN layer formed over a substrate, a second AlGaN layer formed over the first AlGaN layer, an electron transit layer formed over the second AlGaN layer, and an electron supply layer formed over the electron transit layer are provided. A relationship of '0&#x2266;x1&#x3c;x2&#x2266;1' is found when a composition of the first AlGaN layer is represented by AlGaN, and a composition of the second AlGaN layer is represented by AlGaN. Negative charges exist at an upper surface of the AlGaN layer more than positive charges existing at a lower surface of the AlGaN layer.

Compound semiconductor device and manufacturing method thereof

A compound semiconductor device includes: a substrate; an electron transit layer formed over the substrate; an electron supply layer formed over the electron transit layer; and a buffer layer formed between the substrate and the electron transit layer and including AlGaN(0&#x2266;x&#x2266;1), wherein the x value represents a plurality of maximums and a plurality of minimums in the direction of the thickness of the buffer layer, and the variation of x in any area having a 1 nm thickness in the buffer layer is 0.5 or less.

A compound semiconductor device includes: a compound semiconductor layer; a first film formed over the compound semiconductor layer, the first film being in a negatively charged state or a non-charged state at an interface with the compound semiconductor layer; a second film formed over the first film, the second film being in a positively charged state at an interface with the first film; and a gate electrode to be embedded in an opening formed in the second film.

Compound semiconductor device including first film on compound semiconductor layer and second film on first film and method of manufacturing the same

A compound semiconductor device has a buffer layer formed on a conductive SiC substrate, an AlxGa1-xN layer formed on the buffer layer in which an impurity for reducing carrier concentration from an unintentionally doped donor impurity is added and in which the Al composition x is 0&#x3c;x&#x3c;1, a GaN-based carrier transit layer formed on the AlxGa1-xN layer, a carrier supply layer formed on the carrier transit layer, a source electrode and a drain electrode formed on the carrier supply layer, and a gate electrode formed on the carrier supply layer between the source electrode and the drain electrode. Therefore, a GaN-HEMT that is superior in device characteristics can be realized in the case of using a relatively less expensive conductive SiC substrate compared with a semi-insulating SiC substrate.

Method of manufacturing compound semiconductor device

A semiconductor device may include a first semiconductor layer formed on a substrate, a second semiconductor layer formed on the first semiconductor layer, a source electrode and a drain electrode in contact with the first semiconductor layer or the second semiconductor layer, an opening formed in the second semiconductor layer, an insulating film formed on an inner surface of the opening formed in the second semiconductor layer and above the second semiconductor layer, a gate electrode formed in the opening via the insulating film, and a protective film formed on the insulating film and including an amorphous film containing carbon as a major component.

Semiconductor device and method of fabricating the semiconductor device

A compound semiconductor multilayer structure is formed on a Si substrate. The compound semiconductor multilayer structure includes an electrode transit layer, an electrode donor layer formed above the electron transit layer, and a cap layer formed above the electron donor layer. The cap layer contains a first crystal polarized in the same direction as the electron transit layer and the electron donor layer and a second crystal polarized in the direction opposite to the polarization direction of the electron transit layer and the electron donor layer.

Compound semiconductor device and method for fabricating the same

A compound semiconductor device is provided with a substrate, an AlN layer formed over the substrate, an AlGaN layer formed over the AlN layer and larger in electron affinity than the AlN layer, another AlGaN layer formed over the AlGaN layer and smaller in electron affinity than the AlGaN layer. Furthermore, there are provided an i-GaN layer formed over the latter AlGaN layer, and an i-AlGaN layer and an n-AlGaN layer formed over the i-GaN layer.

A semiconductor epitaxial substrate includes: a single crystal substrate; an AlN layer epitaxially grown on the single crystal substrate; and a nitride semiconductor layer epitaxially grown on the AlN layer, wherein an interface between the AlN layer and nitride semiconductor layer has a larger roughness than an interface between the single crystal substrate and AlN layer, and a skewness of the upper surface of the AlN layer is positive.

Compound semiconductor device including aln layer of controlled skewness

A compound semiconductor device includes: an electron transport layer formed over a substrate; an electron supply layer formed over the electron transport layer; and a cap layer formed over the electron supply layer; the cap layer includes a first compound semiconductor layer containing GaN; a second compound semiconductor layer containing AlN, which is formed over the first compound semiconductor layer; a third compound semiconductor layer containing GaN, which is formed over the second compound semiconductor layer; and at least one of a first AlGaN-containing layer and a second AlGaN-containing layer, with the first AlGaN-containing layer formed between the first compound semiconductor layer and the second compound semiconductor layer and the Al content increases toward the second compound semiconductor layer, and the second AlGaN-containing layer formed between the second compound semiconductor layer and the third compound semiconductor layer and the Al content increases toward the second compound semiconductor layer.

Growing community of inventors

Kawasaki, Japan

Kenji Imanishi