Thin-film transistor, liquid crystal display panel, and thin-film transistor manufacturing method

Patent metadata

Field	Value
Publication number	US-10121900-B2
Application number	US-201615100402-A
Country	US
Kind code	B2
Filing date	Mar 31, 2016
Priority date	Mar 11, 2016
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A thin-film transistor, a liquid crystal display panel, and a thin-film transistor manufacturing method are provided. The thin-film transistor includes a base plate and a gate electrode, a gate insulation layer, a source electrode, a drain electrode, a channel layer, first and second ohmic contact layers, a passivation layer, and a pixel electrode that are arranged on the same side of the base plate. The gate insulation layer covers the gate electrode that is on the base plate. The source electrode, the drain electrode, the channel layer, the first and second ohmic contact layers are arranged on the gate insulation layer. The channel layer is arranged between the source electrode and the drain electrode and corresponds to the gate electrode. The first ohmic contact layer is arranged between the source electrode and the channel layer. The second ohmic contact layer is arranged between the drain electrode and the channel layer.

First claim

What is claimed is:

1. A thin-film transistor, comprising a base plate and a gate electrode, a gate insulation layer, a source electrode, a drain electrode, a channel layer, a first ohmic contact layer, a second ohmic contact layer, a passivation layer, and a pixel electrode that are arranged on the same side of the base plate, the gate electrode being arranged on a surface of the base plate and the gate insulation layer covering the gate electrode, the source electrode, the drain electrode, the channel layer, the first ohmic contact layer, and the second ohmic contact layer being arranged on the gate insulation layer, the source electrode and the drain electrode being spaced from each other; the channel layer being arranged between the source electrode and the drain electrode, the channel layer being arranged to correspond to the gate electrode, the first ohmic contact layer being arranged between the source electrode and the channel layer, two opposite ends of the first ohmic contact layer being respectively in contact engagement with an end of the source electrode that faces the channel layer and an end of the channel layer that faces the source electrode, the first ohmic contact layer functioning to reduce contact resistance between the source electrode and the channel layer, the second ohmic contact layer being arranged between the drain electrode and the channel layer, two opposite ends of the second ohmic contact layer being respectively in contact engagement with an end of the drain electrode that faces the channel layer and an end of the channel layer that faces the drain electrode, the second ohmic contact layer functioning to reduce contact resistance between the drain electrode and the channel layer, the first ohmic contact layer, the second ohmic contact layer, and the channel layer being on the same layer, the channel layer being a metal oxide layer, the passivation layer covering the channel layer, the source electrode, the drain electrode, the first ohmic contact layer, and the second ohmic contact layer, the passivation layer being formed with a via corresponding to the drain electrode, the pixel electrode being arranged on the passivation layer and connected, through the via, to the drain electrode;
wherein the gate electrode comprises a first lateral face and a second lateral face opposite to each other, the first lateral face and the second lateral face both intersecting the base plate, the first lateral face being arranged closer to the source electrode than the second lateral face, the first lateral face being coplanar with an end of the channel layer that faces the source electrode, the second lateral face being coplanar with an end of the channel layer that faces the drain electrode.

2. The thin-film transistor as claimed in claim 1 , wherein the channel layer comprises indium gallium zinc oxide (IGZO).

3. The thin-film transistor as claimed in claim 1 , wherein the gate insulation layer comprises a first sub gate insulation layer and a second sub gate insulation layer, the first sub gate insulation layer being set on and covering the gate electrode, the second sub gate insulation layer being set on and covering the first sub gate insulation layer, the first sub gate insulation layer comprising a silicon nitride material, the second sub gate insulation layer comprising a silicon oxide material.

4. A liquid crystal display panel, comprising a thin-film transistor as claimed in claim 1 .

5. A thin-film transistor manufacturing method, comprising:
providing a base plate, wherein the base plate comprises a first surface and a second surface that are opposite to each other;
forming a gate electrode on the first surface, wherein the gate electrode comprises a first lateral face and a second lateral face and the first lateral face and the second lateral face both intersect the base plate;
forming a gate insulation layer covering the gate electrode;
forming a source electrode and a drain electrode that are arranged on the gate insulation layer such that a gap is formed between the source electrode and the drain electrode, wherein a distance from an end of the source electrode that faces the drain electrode to the second lateral surface is greater than a distance from the first lateral surface to the second lateral surface, and a distance from an end of the drain electrode that faces the source electrode to the first lateral surface is greater than a distance from the second lateral surface to the first lateral surface;
forming a first ohmic contact layer, a second ohmic contact layer, and a channel layer that are on the same layer in the gap, wherein the first ohmic contact layer is arranged between the source electrode and the channel layer and two opposite ends of the first ohmic contact layer are respectively in contact engagement with the source electrode and an end of the channel layer that faces the source electrode; and the second ohmic contact layer is arranged between the drain electrode and the channel layer and two opposite ends of the second ohmic contact layer are respectively in contact engagement with the drain electrode and an end of the channel layer that faces the drain electrode, wherein the channel layer comprises a metal oxide layer;
forming a passivation layer to cover the channel layer, the source electrode, the drain electrode, the first ohmic contact layer, and the second ohmic contact layer;
forming a via in the passivation layer to correspond to the drain electrode; and
forming a pixel electrode that is arranged on the passivation layer and is connected, through the via, to the drain electrode.

6. The thin-film transistor manufacturing method as claimed in claim 5 , wherein “forming a first ohmic contact layer, a second ohmic contact layer, and a channel layer that are on the same layer in the gap” comprises:
forming a metal oxide material layer in the gap and in contact engagement with an end of the source electrode that faces the drain electrode and an end of the drain electrode that faces the source electrode; and
irradiating ultraviolet light on the second surface for a predetermined period of time, wherein a portion of the metal oxide layer that is in contact engagement with the source electrode and irradiated with the ultraviolet light forms a first ohmic contact layer and a portion of the metal oxide material layer that is in contact engagement with the drain electrode and irradiated with the ultraviolet light forms a second ohmic contact layer, while a portion of the metal oxide material layer that is not irradiated with the ultraviolet light forms a channel layer.

7. The thin-film transistor manufacturing method as claimed in claim 6 , wherein the ultraviolet light has a wavelength of 150-300 nm and the predetermined period of time of irradiation is 2 hours to 4 hours.

8. The thin-film transistor manufacturing method as claimed in claim 6 , wherein when the second surface is irradiated with ultraviolet light, the ultraviolet light so irradiated perpendicular to the second surface.

9. The thin-film transistor manufacturing method as claimed in claim 5 , wherein “forming a gate insulation layer covering the gate electrode” comprises:
forming a first sub insulation layer set on and covering the gate electrode, wherein the first sub insulation layer comprises a silicon nitride material; and
forming a second sub insulation layer set on and covering the first sub insulation layer, wherein the second sub insulation layer comprises a silicon oxide material.

10. A thin-film transistor, comprising a base plate and a gate electrode, a gate insulation layer, a source electrode, a drain electrode, a channel layer, a first ohmic contact layer, a second ohmic contact layer, a passivati

Assignees

• Shenzhen China Star Optoelect
• Shenzhen China Star Optoelect

Inventors

• Hu Xiaobo

Classifications

• H10P34/00

  Irradiation with electromagnetic or particle radiation of wafers, substrates or parts of devices · CPC title

• H01L29/66969

  Electricity · mapped topic

• H01L29/7869

  Electricity · mapped topic

• H01L29/423

  Electricity · mapped topic

• G02F1/1368

  in which the switching element is a three-electrode device {(G02F1/136277 takes precedence)} · CPC title