Sharp Kabushiki Kaisha Corporation

Hiromi Sakamoto

Saori Kurogane

Yasushi Kubota

Masahiro Adachi

Naoki Makita

Masao Moriguchi

Narihiro Morosawa

In a production method of a semiconductor device, a catalyst element, e.g. Ni, is added to an amorphous silicon film, formed on a substrate with an insulating surface, for promoting crystallization of the amorphous silicon film. Thereafter, the amorphous silicon film is subjected to heat treatment to cause crystal growth therein. Next, the crystal growth is stopped in a state where minute amorphous regions (uncrystallized regions) remain in the film. Next, the silicon film is irradiated with strong light (laser light) so as to be further crystallized. As a result, a crystalline silicon film that has high quality and is excellent in uniformity is obtained.

Method of producing semiconductor device

A thin film transistor of this invention includes: a source and drain regions formed on an insulating base region; and a conductive layer connected to the source and drain regions. The conductive layer has a layered structure of an Al-containing metal film and an N-containing Mo film.

Thin film transistor

A terminal section for anodic oxidation made of a metal which is the same kind of a metal as a light shielding film is formed on an end of a light transmitting substrate. Then, wiring space for the terminal section for anodic oxidation is masked, and a first insulating film, a semiconductor layer and a second insulating film are deposited by the sputtering method or the CVD method, for example. Moreover, an electrically conductive material to be a gate electrode is laminated and patterned on the second insulating film and the terminal section for anodic oxidation so that the wiring space for the terminal section for anodic oxidation is exposed. As a result, the gate electrode which is electrically connected to the terminal section for anodic oxidation is formed. By making wiring in the wiring space for the terminal section for anodic oxidation, the gate electrode is anodically oxidized. With the above method, only the wiring space for the terminal section for anodic oxidation is easily exposed, and the terminal section for anodic oxidation can be electrically connected to the gate electrode. Therefore, with the above method, a number of the processes can be decreased, the process for anodic oxidation can be simplified and cost of production can be reduced. Moreover, a thin film transistor with high reliability can be provided.

Method of manufacturing thin film transistor

A thin-film transistor circuit, which is used as a driving circuit for driving pixels in an image display, is constituted of a plurality of thin-film transistors that are formed on an insulating substrate. In each thin-film transistor, a conductive electrode is placed so as to face a gate electrode with a channel region of a polycrystal silicon thin-film that forms an active layer located in between. Here, a constant voltage is applied to the conductive electrode. When threshold voltage is shifted by applying a voltage to the conductive electrode, it is possible to allow the absolute value of the threshold voltage of n-channel-type transistors and the absolute value of the threshold voltage of p-channel-type transistors to become virtually equal to each other. Moreover, it is possible to properly set the threshold voltage in accordance with factors such as the channel length of the thin-film transistors, the types of circuits that are constituted of the thin-film transistors and voltages to be applied to the thin-film transistors. Thus, it becomes possible to remarkably improve the characteristics of thin-film transistor circuits, such as operation speeds and holding characteristics.

Thin-film transistor circuit and image display

A semiconductor device formed on an insulating substrate of the present invention includes: a gate wiring provided on the insulating substrate; a first insulating film provided so as to cover the gate wiring; an upper electrode formed so as to face the gate wiring in such a manner that the first insulating film is interposed therebetween; a second insulating film provided so as to cover the upper electrode; and another electrode formed on the second insulating film, wherein the upper electrode is electrically connected to the another electrode via a contact hole formed through the second insulating film, a storage capacitor is formed of a structure including the upper electrode, the first insulating film, and the gate wiring opposing the upper electrode through the first insulating film, the upper electrode and the gate wiring have substantially the same width.

Growing community of inventors

Kashiba, Japan

Hiromi Sakamoto