Semiconductor Energy Laboratory Co., Ltd.

Mari Terashima

Hideaki Kuwabara

Yasuyuki Arai

Shinya Sasagawa

Hiromichi Godo

Motomu Kurata

Junpei Sugao

Satohiro Okamoto

Eriko Nishida

Shunpei Yamazaki

Hiroyuki Miyake

Junichiro Sakata

Junichi Koezuka

Yuhei Sato

Naoto Yamade

Kyoko Yoshioka

An object is to provide a semiconductor device including an oxide semiconductor in which miniaturization is achieved while favorable characteristics are maintained. The semiconductor includes an oxide semiconductor layer, a source electrode and a drain electrode in contact with the oxide semiconductor layer, a gate electrode overlapping with the oxide semiconductor layer, a gate insulating layer provided between the oxide semiconductor layer and the gate electrode, and an insulating layer provided in contact with the oxide semiconductor layer. A side surface of the oxide semiconductor layer is in contact with the source electrode or the drain electrode. An upper surface of the oxide semiconductor layer overlaps with the source electrode or the drain electrode with the insulating layer interposed between the oxide semiconductor layer and the source electrode or the drain electrode.

Semiconductor device

To provide a highly reliable semiconductor device including a transistor using an oxide semiconductor. After a source electrode layer and a drain electrode layer are formed, an island-like oxide semiconductor layer is formed in a gap between these electrode layers so that a side surface of the oxide semiconductor layer is covered with a wiring, whereby light is prevented from entering the oxide semiconductor layer through the side surface. Further, a gate electrode layer is formed over the oxide semiconductor layer with a gate insulating layer interposed therebetween and impurities are introduced with the gate electrode layer used as a mask. Then, a conductive layer is provided on a side surface of the gate electrode layer in the channel length direction, whereby an Lov region is formed while maintaining a scaled-down channel length and entry of light from above into the oxide semiconductor layer is prevented.

Method for manufacturing a semiconductor device

A highly reliable semiconductor device which is formed using an oxide semiconductor and has stable electric characteristics is provided. A semiconductor device which includes an amorphous oxide semiconductor layer including a region containing oxygen in a proportion higher than that in the stoichiometric composition, and an aluminum oxide film provided over the amorphous oxide semiconductor layer is provided. The amorphous oxide semiconductor layer is formed as follows: oxygen implantation treatment is performed on a crystalline or amorphous oxide semiconductor layer which has been subjected to dehydration or dehydrogenation treatment, and then thermal treatment is performed on the oxide semiconductor layer provided with an aluminum oxide film at a temperature lower than or equal to 450&#xb0; C.

A semiconductor device is provided in which a pixel portion and a driver circuit each including a thin film transistor are provided over one substrate; the thin film transistor in the pixel portion includes a gate electrode layer, a gate insulating layer, an oxide semiconductor layer having an end region with a small thickness, an oxide insulating layer in contact with part of the oxide semiconductor layer, source and drain electrode layers, and a pixel electrode layer; the thin film transistor in the pixel portion has a light-transmitting property; and source and drain electrode layers of the thin film transistor in the driver circuit portion are formed using a conductive material having lower resistance than a material of the source and drain electrode layer in the pixel portion.

Semiconductor device and manufacturing method thereof

Growing community of inventors

Ayase, Japan

Mari Terashima