Thin film transistor, manufacturing method thereof, and display device having the same

Patent metadata

Field	Value
Publication number	US-10804299-B2
Application number	US-201916275829-A
Country	US
Kind code	B2
Filing date	Feb 14, 2019
Priority date	Nov 4, 2016
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

A thin film transistor includes a first blocking layer disposed on a substrate, and an active pattern disposed on the first blocking layer. The active pattern includes a source region, a drain region, and a channel region disposed between the source region and the drain region. The thin film transistor further includes a gate electrode disposed on the active pattern. The channel region corresponds to a portion of the active pattern overlapped by the gate electrode. The thin film transistor additionally includes a source electrode connected to the source region, and a drain electrode connected to the drain region. The active pattern includes a first part and a second part. The first part partially overlaps with the first blocking layer, and the first part and the second part have different thicknesses from each other.

First claim

What is claimed is:

1. A display device comprising:
a display element; and
a thin film transistor connected to the display element,
wherein the thin film transistor includes:
a first blocking layer disposed on a substrate;
an active pattern disposed on the first blocking layer, wherein the active pattern includes a source region, a drain region, and a channel region disposed between the source region and the drain region;
a gate electrode disposed on the active pattern, wherein the channel region corresponds to a portion of the active pattern overlapping by the gate electrode; and
a source electrode connected to the source region, and a drain electrode connected to the drain region,
wherein the active pattern includes a first part and a second part, wherein the first part partially overlaps with the first blocking layer, and the first part and the second part have different thicknesses from each other, wherein a first portion of the channel region overlapping a first portion of the gate electrode does not overlap the first blocking layer.

2. The display device of claim 1 , wherein the second part of the active pattern does not overlap with the first blocking layer.

3. The display device of claim 2 , wherein a thickness of the first part of the active pattern is less than a thickness of the second part of the active pattern.

4. The display device of claim 1 , wherein the drain region partially overlaps with the first blocking layer.

5. The display device of claim 4 , wherein the active pattern further comprises a drain-channel contact part disposed between the drain region and the channel region,
wherein the drain-channel contact part overlaps with the first blocking layer.

6. The display device of claim 1 , further comprising a second blocking layer partially overlapping with the drain region and the channel region, and
wherein the first blocking layer partially overlaps with the source region and the channel region.

7. The display device of claim 6 , wherein the first blocking layer and the second blocking layer are disposed in the same layer.

8. The display device of claim 6 , wherein the active pattern further comprises a source-channel contact part disposed between the source region and the channel region, and a drain-channel contact part disposed between the drain region and the channel region,
wherein the source-channel contact part overlaps with the first blocking layer, and the drain-channel contact part overlaps with the second blocking layer.

9. The display device of claim 1 , wherein the display element includes:
a first electrode connected to the drain electrode of the thin film transistor;
an emitting layer disposed on the first electrode; and
a second electrode disposed on the emitting layer.

10. The display device of claim 1 , wherein a thickness of, the first pan of the active pattern extending from a first edge of the first blocking layer to a second edge of the first blocking layer is constant and less than a thickness of the second part of the active pattern.

11. A display device comprising:
a display element; and
a thin film transistor connected to the display element,
wherein the thin film transistor includes:
a first blocking layer disposed on a substrate;
an active pattern disposed on the first blocking layer, wherein the active pattern includes a source region, a drain region, and a channel region disposed between the source region and the drain region;
a gate electrode disposed on the active pattern, wherein the channel region corresponds to a portion of the active pattern overlapping by the gate electrode; and
a source electrode connected to the source region, and a drain electrode connected to the drain region,
wherein the active pattern includes a first part and a second part, wherein the first part partially overlaps with the first blocking layer, and the first part and the second part have different thicknesses from each other, wherein the drain region partially overlaps with the first blocking layer, wherein the active pattern further comprises a drain-channel contact part disposed between the drain region and the channel region,
wherein the drain-channel contact part overlaps with the first blocking layer, wherein the drain-channel contact part is covered by the first blocking layer to block light that is incident onto a surface of the substrate, on which the active pattern is not disposed.

12. The display device of claim 11 , wherein the drain-channel contact part partially extends into the channel region from a point at which the channel region and the drain region are in contact with each other.

13. The display device of claim 12 , wherein the drain-channel contact part has a width of about 3.5 μm or more.

14. A display device comprising:
a display element; and
a thin film transistor connected to the display element,
wherein the thin film transistor includes:
a first blocking layer disposed on a substrate;
an active pattern disposed on the first blocking layer, wherein the active pattern includes a source region, a drain region, and a channel region disposed between the source region and the drain region;
a gate electrode disposed on the active pattern, wherein the channel region corresponds to a portion of the active pattern overlapping by the gate electrode;
a source electrode connected to the source region, and a drain electrode connected to the drain region, wherein the active pattern includes a first part and second part, wherein the first part partially overlaps with the first blocking layer, and the first part and the second part have different thicknesses from each other; and
a second blocking layer partially overlapping with the drain region and the channel region,
wherein the first blocking layer partially overlaps with the source region and the channel region,
wherein the active pattern further comprises a source-channel contact part disposed between the source region and the channel region, and a drain-channel contact part disposed between the drain region and the channel region,
wherein the source-channel contact part overlaps with the first blocking layer, and the drain-channel contact part overlaps with the second blocking layer, wherein the source-channel contact part is covered by the first blocking layer to block light that is incident onto a surface of the substrate, on which the active pattern is not disposed, and
wherein the drain-channel contact part is covered by the second blocking layer to block light that is incident onto the surface of the substrate, on which the active pattern is not disposed.

15. The display device of claim 14 , wherein the source-channel contact part partially extends into the channel region from a point at which the channel region and the source region are in contact with each other, and
wherein the drain-channel contact part partially extends into the channel region from a point which the channel region and the drain region are in contact with each other.

16. The display device of claim 15 , wherein each of the source-channel contact part and the drain-channel contact part has a width of about 3.5 μm or more.

Assignees

• Samsung Display Co Ltd

Inventors

• Lee Jun Hee
• Bae In Jun

Classifications

• H10D30/6757

  characterised by the structure of the channel, e.g. transverse or longitudinal shape or doping profile (TFTs having channel structures for preventing kink or snapback effects H10D30/6708; TFTs having lightly-doped source or drain extensions H10D30/6715) · CPC title

• H10D86/0212

  comprising manufacture, treatment or coating of substrates · CPC title

• H10D86/421

  having a particular composition, shape or crystalline structure of the active layer · CPC title

• H10D30/6723

  having light shields · CPC title

• H10D30/6713 Primary

  characterised by the properties of the source or drain regions, e.g. compositions or sectional shapes · CPC title