Semiconductor Energy Laboratory Co., Ltd.

Kabushiki Kaisha Toshiba

Keisuke Murayama

Daisuke Matsubayashi

Junichi Koezuka

Toshinari Sasaki

Yukinori Shima

Hajime Tokunaga

Shunpei Yamazaki

Jun Koyama

Hiroyuki Miyake

Hideaki Shishido

Hiromichi Godo

Norihisa Arai

Masayuki Akou

To reduce defects in an oxide semiconductor film in a semiconductor device. To improve the electrical characteristics and the reliability of a semiconductor device including an oxide semiconductor film. In a semiconductor device including a transistor including a gate electrode formed over a substrate, a gate insulating film covering the gate electrode, a multilayer film overlapping with the gate electrode with the gate insulating film provided therebetween, and a pair of electrodes in contact with the multilayer film, a first oxide insulating film covering the transistor, and a second oxide insulating film formed over the first oxide insulating film, the multilayer film includes an oxide semiconductor film and an oxide film containing In or Ga, the first oxide insulating film is an oxide insulating film through which oxygen is permeated, and the second oxide insulating film is an oxide insulating film containing more oxygen than that in the stoichiometric composition.

Semiconductor device and method for manufacturing the same

A transistor includes oxide semiconductor stacked layers between a first gate electrode layer and a second gate electrode layer through an insulating layer interposed between the first gate electrode layer and the oxide semiconductor stacked layers and an insulating layer interposed between the second gate electrode layer and the oxide semiconductor stacked layers. The thickness of a channel formation region is smaller than the other regions in the oxide semiconductor stacked layers. Further in this transistor, one of the gate electrode layers is provided as what is called a back gate for controlling the threshold voltage. Controlling the potential applied to the back gate enables control of the threshold voltage of the transistor, which makes it easy to maintain the normally-off characteristics of the transistor.

Semiconductor device comprising conductive layers functioning as first and second gate electrodes of a transistor

Semiconductor device comprising various thin-film transistors

In a semiconductor device including a transistor including a gate electrode formed over a substrate, a gate insulating film covering the gate electrode, a multilayer film overlapping with the gate electrode with the gate insulating film provided therebetween, and a pair of electrodes in contact with the multilayer film, a first oxide insulating film covering the transistor, and a second oxide insulating film formed over the first oxide insulating film, the multilayer film includes an oxide semiconductor film and an oxide film containing In or Ga, the oxide semiconductor film has an amorphous structure or a microcrystalline structure, the first oxide insulating film is an oxide insulating film through which oxygen is permeated, and the second oxide insulating film is an oxide insulating film containing more oxygen than that in the stoichiometric composition.

Semiconductor device comprising stacked oxide semiconductor layers

Semiconductor device comprising an oxide semiconductor

Semiconductor device

Semiconductor device including oxide semiconductor stacked layers

A semiconductor device includes a transistor including a gate electrode over a substrate, a gate insulating film covering the gate electrode, a multilayer film overlapping with the gate electrode with the gate insulating film provided therebetween, and a pair of electrodes in contact with the multilayer film, and an oxide insulating film covering the transistor. The multilayer film includes an oxide semiconductor film and an oxide film containing In or Ga, the oxide insulating film contains more oxygen than that in the stoichiometric composition, and in the transistor, by a bias-temperature stress test, threshold voltage does not change or the amount of the change in a positive direction or a negative direction is less than or equal to 1.0 V, preferably less than or equal to 0.5 V.

Growing community of inventors

Kanagawa, Japan

Keisuke Murayama