Rohm Co., Ltd.

Shuhei Mitani

Yuki Nakano

Heiji Watanabe

Takayoshi Shimura

Takuji Hosoi

Takashi Kirino

Mineo Miura

Takashi Nakamura

Ryota Nakamura

Masatoshi Aketa

Katsuhisa Nagao

Keiji Okumura

Hirokazu Asahara

A semiconductor device includes a semiconductor layer of a first conductivity type. A well region that is a second conductivity type well region is formed on a surface layer portion of the semiconductor layer and has a channel region defined therein. A source region that is a first conductivity type source region is formed on a surface layer portion of the well region. A gate insulating film is formed on the semiconductor layer and has a multilayer structure. A gate electrode is opposed to the channel region of the well region where a channel is formed through the gate insulating film.

Semiconductor device

A semiconductor device includes a semiconductor layer made of first conductivity type semiconductor layer; a second conductivity type well region formed on the semiconductor layer and having a channel region; a first conductivity type source region formed on the well region and including a first region adjacent to the well region and a second region adjacent to the first region; a gate insulating film formed on the semiconductor layer and having a first portion that contacts the first region; a second portion that contacts the well region and that has a thickness that is the same as that of the first portion; and a third portion that contacts the second region and that has a thickness that is greater than that of the first portion; and a gate electrode formed on the gate insulating film and opposed to the channel region where a channel is formed through the gate insulating film.

A semiconductor device according to the present invention has a MIS structure that includes a semiconductor layer, a gate insulating film in contact with the semiconductor layer, and a gate electrode formed on the gate insulating film, and the gate insulating film includes an AlON layer with a nitrogen composition of 5% to 40%. A semiconductor device is thereby provided with which electron trapping in the gate insulating film can be reduced and shifting of a threshold voltage Vcan be suppressed.

[Problem] To provide an SiC semiconductor device, with which stabilization of high-temperature operation can be achieved by decreasing mobile ions in a gate insulating film, and a method for manufacturing the SiC semiconductor device. [Solution Means] A semiconductor devicehas an MIS structure including an SiC epitaxial layer, a gate insulating filmand a gate electrodeformed on the gate insulating film. A gate insulating filmincludes a silicon oxide film in contact with the SiC epitaxial layer. In the MIS structure, an area density Qof positive mobile ions in the gate insulating filmis made no more than 1&#xd7;10cm.

Semiconductor device and method for manufacturing same

A semiconductor device includes a semiconductor layer made of first conductivity type SiC; a second conductivity type well region formed on the semiconductor layer and having a channel region; a first conductivity type source region formed on the well region and including a first region adjacent to the well region and a second region adjacent to the first region; a gate insulating film formed on the semiconductor layer and having a first portion that contacts the first region; a second portion that contacts the well region and that has a thickness that is the same as that of the first portion; and a third portion that contacts the second region and that has a thickness that is greater than that of the first portion; and a gate electrode formed on the gate insulating film and opposed to the channel region where a channel is formed through the gate insulating film.

A SiC semiconductor device includes a SiC semiconductor layer having a first-conductivity-type impurity, a field insulation film formed on a front surface of the SiC semiconductor layer and provided with an opening for exposing therethrough the front surface of the SiC semiconductor layer, an electrode connected to the SiC semiconductor layer through the opening of the field insulation film, and a guard ring having a second-conductivity-type impurity and being formed in a surface layer portion of the SiC semiconductor layer to make contact with a terminal end portion of the electrode connected to the SiC semiconductor layer. A second-conductivity-type impurity concentration in a surface layer portion of the guard ring making contact with the electrode is smaller than a first-conductivity-type impurity concentration in the SiC semiconductor layer.

SiC semiconductor device

A semiconductor device includes a first conductive-type semiconductor layer, a second conductive-type body region formed in a surficial portion of the semiconductor layer, a first conductive-type source region formed in a surficial portion of the body region, a gate insulating film provided on the semiconductor layer and containing nitrogen atoms, the gate insulating film including a first portion in contact with the semiconductor layer outside the body region, a second portion in contact with the body region, and a third portion in contact with the source region, and a gate electrode provided on the gate insulating film in an area extending across the semiconductor layer outside the body region, the body region, and the source region. The third portion of the gate insulating film has a thickness greater than the thickness of the first portion and the thickness of the second portion.

Growing community of inventors

Kyoto, Japan

Shuhei Mitani