Method for forming poly-silicon thin-film device

Abstract

A method for forming a poly-silicon thin-film device, comprising steps of: providing a substrate; forming a poly-silicon film on the substrate, the poly-silicon film comprising a plurality of poly-silicon grains oriented in a grain growth direction; and forming a plurality of thin-film transistors, each of the thin-film transistors including a channel region formed from a portion of the poly-silicon film; wherein at least one channel region has an equivalent parallel channel region with a channel direction parallel to the grain growth direction and an equivalent perpendicular channel region with a channel direction perpendicular to the grain growth direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, spirits and advantages of the preferred embodiments of the present invention will be readily understood by the accompanying drawings and detailed descriptions, wherein:

FIG. 1A is a conventional system for forming a p-Si film using sequential lateral solidification (SLS);

FIG. 1B is a top view of a p-Si film formed using the system in FIG. 1A;

FIG. 2A is a top view of a mask used in a SLS process disclosed in U.S. Pat. No. 6,521,473;

FIG. 2B is a top view of a p-Si film formed using the method disclosed in U.S. Pat. No. 6,521,473 and transistors formed thereon;

FIG. 3 is a top view of a transistor layout design used in a method for forming a poly-silicon thin-film device according to a first embodiment of the present invention;

FIG. 4 is a top view of a transistor layout design used in a method for forming a poly-silicon thin-film device according to a second embodiment of the present invention;

FIG. 5 is a top view of a transistor layout design used in a method for forming a poly-silicon thin-film device according to a third embodiment of the present invention; and

FIG. 6 is a top view of a transistor layout design used in a method for forming a poly-silicon thin-film device according to a fourth embodiment of the present invention.

Claims

1. A method for forming a poly-silicon thin-film device, comprising steps of: providing a substrate;forming a poly-silicon film on the substrate, the poly-silicon film comprising a plurality of poly-silicon grains oriented in a grain growth direction; andforming a plurality of thin-film transistors, each of the thin-film transistor including a channel region formed from a portion of the poly-silicon film;wherein at least one channel region has an equivalent parallel channel region with a channel direction parallel to the grain growth direction and an equivalent perpendicular channel region with a channel direction perpendicular to the grain growth direction.

2. The method as recited in claim 1, wherein the poly-silicon film has a plurality of primary grain boundaries perpendicular to the grain growth direction and a plurality of secondary grain boundaries parallel to the grain growth direction.

3. The method as recited in claim 1, wherein the poly-silicon film is formed using sequential lateral solidification (SLS) with at least one laser irradiation.

4. The method as recited in claim 1, wherein the channel region is L-shaped.

5. The method as recited in claim 1, wherein the channel region is multi-L shaped.

6. The method as recited in claim 1, wherein the channel region is fan-shaped.

7. The method as recited in claim 1, wherein the channel region is circular-shaped.

8. The method as recited in claim 1, wherein the poly-silicon thin-film device is a liquid crystal display.

9. The method as recited in claim 1, wherein the poly-silicon thin-film device is a driving circuit for a display.

10. The method as recited in claim 1, wherein the poly-silicon thin-film device is a pixel unit for a display.