Thin film transistor, manufacturing method thereof, and circuit and liquid crystal display device using the thin film transistor

• US 6,333,520 B1
• Filed: 01/19/2000
• Issued: 12/25/2001
• Est. Priority Date: 06/28/1996
• Status: Expired due to Term

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Inoue, Satoshi
• Primary Examiner(s): NGO, NGAN V
• Application Number:
  US09/488,038
• Time in Patent Office: 706 Days
• Field of Search: 257/57, 257/59, 257/66, 257/72, 257/347, 257/350, 257/401
• US Class Current: 257/72
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

A thin film transistor has a structure capable of decreasing deterioration in Vgs-Ids characteristics. The thin film transistor has a source region composed of an N-type impurity-diffused region, a drain region, and a gate electrode, and a channel region formed directly below the gate electrode. To the source region and the drain region are connected a source electrode and a drain electrode, respectively, through a plurality of contact holes. In the channel region are formed a plurality of P-type impurity-diffused regions at constant intervals.

Claims

1. A thin film transistor comprising:

a substrate; and

a non-single crystal silicon thin film on the substrate, the non-single crystal silicon thin film forming a channel region, a first region and a second region of a first conduction type formed in the non-single crystal silicon thin film separated by the channel region,

wherein a width of at least the channel region of the non-single crystal silicon thin film is larger than a minimum width of the first region and the second region.

2. The thin film transistor according to claim 1, wherein the width of the channel region is 50 μ

m or more.

3. The thin film transistor according to claim 1, wherein the width of the channel region is 100 μ

m or more.

4. The thin film transistor according to claim 1, wherein the first conduction type is an N-type.

5. The thin film transistor according to claim 1, wherein the non-single crystal silicon thin film is a polycrystalline silicon thin film.

6. The thin film transistor according to claim 5, wherein the polycrystalline thin film is formed by a low temperature process.

7. A circuit comprising the thin film transistor according to claim 1.

8. A built-in driver circuit type liquid crystal display device comprising the thin film transistor according claim 1.

9. The built-in driver circuit type liquid crystal display device according to claim 8, wherein the thin film transistor is used in a circuit element.

10. The built-in driver circuit type liquid crystal display device according to claim 9, wherein the thin film transistor is used as an analog switch in the circuit element.