THIN FILM FIELD EFFECT TRANSISTOR AND DISPLAY

• US 20100163863A1
• Filed: 06/24/2009
• Published: 07/01/2010
• Est. Priority Date: 06/24/2008
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: YAEGASHI, Hiroyuki
• Granted Patent: US 8,497,502 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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 thin film field effect transistor includes at least: a substrate; and a gate electrode, a gate insulating layer, an active layer, a source electrode and a drain electrode, and a protective layer provided on the substrate in this order from the substrate side. The active layer is a layer containing an amorphous oxide containing at least one metal selected from the group consisting of In, Sn, Zn and Cd. The thin film field effect transistor further includes, between the active layer and at least one of the source electrode or the drain electrode, an electric resistance layer containing an oxide or nitride containing at least one metal selected from the group consisting of Ga, Al, Mg, Ca and Si.

Claims

1. A thin film field effect transistor comprising at least:

a substrate; and

a gate electrode, a gate insulating layer, an active layer, a source electrode and a drain electrode, and a protective layer provided on the substrate in this order from the substrate side, wherein the active layer is a layer containing an amorphous oxide containing at least one metal selected from the group consisting of In, Sn, Zn and Cd, and the thin film field effect transistor further comprises, between the active layer and at least one of the source electrode or the drain electrode, an electric resistance layer containing an oxide or nitride containing at least one metal selected from the group consisting of Ga, Al, Mg, Ca and Si.

2. The thin film field effect transistor according to claim 1, wherein the electric resistance layer is disposed between the protective layer and the active layer.

3. The thin film field effect transistor according to claim 1, wherein the protective layer is a resin layer.

4. The thin film field effect transistor according to claim 1, wherein the protective layer includes a photosensitive resin.

5. The thin film field effect transistor according to claim 2, wherein at least one edge portion of the active layer is covered with the electric resistance layer, and the protective layer and the active layer do not directly contact with each other at the edge portion.

6. The thin film field effect transistor according to claim 1, wherein an electric conductivity of the active layer is 10⁻

10 Scm<sup>−

1</sup> or more but less than 10¹ Scm<sup>−

1</sup>.

7. The thin film field effect transistor according to claim 1, wherein a ratio of an electric conductivity of the active layer relative to an electric conductivity of the electric resistance layer (electric conductivity of active layer/electric conductivity of electric resistance layer) is from 10² to 10⁸.

8. The thin film field effect transistor according to claim 1, wherein the active layer comprises an amorphous oxide which contains at least In.

9. The thin film field effect transistor according to claim 8, wherein the amorphous oxide further contains Zn.

10. The thin film field effect transistor according to claim 1, wherein the electric resistance layer contains an oxide or nitride of at least one metal selected from the group consisting of Ga, Al and Mg.

11. The thin film field effect transistor according to claim 10, wherein the electric resistance layer contains an oxide of at least one metal selected from the group consisting of Ga, Al and Mg.

12. The thin film field effect transistor according to claim 1, wherein the substrate is a flexible substrate.

13. A display comprising:

a pair of electrodes;

a light-emitting element provided between the electrodes and including an organic compound layer including at least a light emitting layer; and

the thin film field effect transistor for driving the light-emitting element according to claim 1.