Oki Electric Industry Co., Ltd.

Lapis Semiconductor Co., Ltd.

Oki Semiconductor Co., Ltd.

Masao Tsujimoto

Ikuo Kurachi

Takaharu Nakamura

Tetsuhiro Maruyama

Yasushi Sato

Kenichi Furuta

Yuuki Doi

Takaaki Kodaira

Toshiyuki Orita

Takao Kaji

Tsuyoshi Inoue

Tomomi Yamanobe

Toshifumi Kobe

Masahiro Haraguchi

Yuuichi Kaneko

Nobuhiro Terada

Hiroki Kuroki

Makoto Higashihira

Kiyofumi Kondou

A semiconductor device, including: a semiconductor substrate formed of silicon carbide, components being formed at one surface of the semiconductor substrate; a periphery portion disposed at a pre-specified region of a periphery of the semiconductor substrate, the components not being formed at the periphery portion; and a plurality of trenches or portions of trenches formed at the periphery portion, an interior of each of the trenches being filled with a material with a different coefficient of thermal expansion from the silicon carbide.

Semiconductor device and semiconductor wafer

The disclosure reduces the risk of collapse of the wall surrounding the trench and suppresses the withstand voltage fluctuation that accompanies the manufacturing variation for a semiconductor device having a super junction structure. The semiconductor device includes a drift layer of a first conductivity type and a plurality of embedded parts embedded in the drift layer. The embedded parts are of a second conductivity type different from the first conductivity type, and the embedded parts are arranged with a first direction as a longitudinal direction and spaced from each other along a second direction that intersects the first direction. A width of each of the embedded parts in the second direction changes continuously along the first direction.

Semiconductor device having super junction structure with varying width

The object is simplification of a manufacturing process for nonvolatile memory by reducing additional processes for forming a charge storage structure, and downsizing of nonvolatile memory. The solution is a manufacturing method for semiconductor memory device including a process for forming sequentially a first oxide film, a first nitride filmon a semiconductor substrate, a process for removing the first oxide filmand the first nitride filmin an element isolating regionB, a process for overhanging the first nitride filmover the first oxide filmby removing the edge of the first oxide filmby cleaning or wet etching, a process for forming a first insulating film(element isolating insulating film) so that a lower density parthaving a lower film density than other parts thereof can be formed in the side part of the fist oxide film, a process for exposing the lower density part, a process for forming a hole in the first insulating filmby eroding the lower concentration partusing cleaning or wet etching, and a process for forming charge storage film in the hole.

Semiconductor memory device and manufacturing method for semiconductor device

Semiconductor memory device and manufacturing method for semiconductor memory device

The present invention provides a method of evaluating a tunnel insulating film of a first MOS FET having a semiconductor substrate, a control gate, a floating gate and a tunnel insulating film formed between the semiconductor substrate and the floating gate which is injected with electrons from the semiconductor substrate by applying a direct current voltage to the control gate. The method is achieved by preparing a second MOS FET having a tunnel insulating film formed on a semiconductor substrate in the same batch process of forming the tunnel insulating film in the first MOS FET, measuring a subthreshold swing of the second MOS FET, applying a direct current electric field to the tunnel insulating film in the second MOS FET for a predetermined time, remeasuring the subthreshold swing of the second MOS FET, and evaluating the tunnel insulating film in the first MOS FET by using a change of the subthreshold swing before and after the applying step.

Method of evaluating a tunnel insulating film

Growing community of inventors

Miyazaki, Japan

Masao Tsujimoto