OXIDE SEMICONDUCTOR THIN-FILM TRANSISTOR

• US 20100200857A1
• Filed: 11/27/2008
• Published: 08/12/2010
• Est. Priority Date: 12/04/2007
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Shimada, Mikio
• Granted Patent: US 8,304,773 B2
• Time in Patent Office: Days
• US Class Current: 257/59
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A transistor includes a gate electrode, a gate insulating layer, a semiconductor layer including an amorphous oxide, source-drain electrodes, and a protective layer on a substrate. The semiconductor layer includes a first region corresponding to a region in which the source-drain electrodes are formed, and a second region not corresponding to the region in which the source-drain electrodes are formed. At least the first region includes a crystalline component having a composition different from the composition of the amorphous oxide in the second region.

Claims

1. A thin-film transistor comprising a gate electrode, a gate insulating layer, a semiconductor layer comprising an amorphous oxide, source-drain electrodes, and a protective layer, wherein:

the semiconductor layer comprises

a first region corresponding to a region in which the source-drain electrodes are formed, and

a second region not corresponding to the region in which the source-drain electrodes are formed; and

at least the first region comprises a crystalline component having a composition different from the composition of the amorphous oxide in the second region.

2. The thin-film transistor according to claim 1, wherein:

the crystalline component contains a metal contained in the semiconductor layer; and

the proportion of the metal per unit volume in the crystalline component is larger than the proportion of the metal per unit volume in the first region.

3. The thin-film transistor according to claim 1, wherein the semiconductor layer is an amorphous oxide semiconductor containing at least one of In, Sn, Zn and Ga.

4. A display device using the thin-film transistor according to claim 1.