Manufacturing method of liquid crystal display device
View Patent ↗A manufacturing method of a thin film transistor of a liquid crystal display device using 3-mask includes forming a gate electrode over a substrate, consecutively forming a gate insulating layer and an active layer, forming a first photoresist pattern, removing an active layer formed at a source/drain region, ashing the first photoresist pattern to expose a part of an active region, forming a source/drain electrode, forming a passivation layer, forming a second photoresist pattern that exposes a pixel region over the passivation layer; forming a pixel region by using the second photoresist pattern as a mask, side-etching a part of the passivation layer to expose a part of the drain electrode, forming a pixel electrode material over the second photoresist pattern and the pixel region, and simultaneously removing the second photoresist pattern and the pixel electrode material formed thereon to form a pixel electrode.
1. A method for manufacturing a liquid crystal display device comprising:
forming a gate electrode over a substrate;
consecutively forming a gate insulating layer and an active layer over the gate electrode;
depositing a photoresist over the active layer and performing a photolithography process to form a first photoresist pattern, and then removing the active layer formed at a source/drain region;
ashing the first photoresist pattern to expose a part of an active region;
forming a source/drain electrode at the source/drain region;
forming a passivation layer on the substrate including the source/drain electrode;
forming a second photoresist pattern that exposes a pixel region on the passivation layer;
forming a pixel region by using the second photoresist pattern as a mask;
side-etching a part of the passivation layer thus to expose a part of the drain electrode;
forming a pixel electrode material over the second photoresist pattern and the pixel region; and
simultaneously removing the second photoresist pattern and the pixel electrode material formed thereon to form a pixel electrode.
2. The method of claim 1 , wherein the step of removing the active layer formed at the source/drain region comprises:
depositing a photoresist over the active layer;
applying a mask to the photoresist, exposing, developing, and thereby forming a photoresist pattern where the source/drain region is defined; and
applying the photoresist pattern as a mask.
3. The method of claim 1 , wherein the step for forming the active layer comprises:
forming a semiconductor layer over the gate insulating layer; and
forming a high-concentration impurity layer over the semiconductor layer.
4. The method of claim 1 , wherein the step of forming the source/drain electrode at the source/drain region comprises:
forming a conductive layer over the photoresist pattern where the source/drain region is defined;
simultaneously removing the photoresist pattern and the conductive layer formed thereon by a lift-off process; and
removing the high-concentrated impurity layer formed above the channel region.
5. The method of claim 4 , wherein the photoresist pattern is formed above the channel region and the pixel region.
6. The method of claim 1 , wherein in the step for side-etching a part of the passivation layer thus to expose a part of the drain electrode, the passivation layer is side-etched by using fluorine-containing gas.
7. The method of claim 1 , wherein the step for side-etching a part of the passivation layer to expose a part of the drain electrode further comprises removing a part of the active layer remaining at a side surface of the source electrode by side-etching.
8. The method of claim 7 , wherein the active layer is removed by using chlorine ion-containing gas.
9. The method of claim 1 , wherein the pixel electrode material and the photoresist pattern formed thereunder are simultaneously removed by a lift-off process.
10. The method of claim 1 , wherein in the step for forming a pixel electrode material on the photoresist pattern and the pixel region, the pixel electrode material is formed over a part of the drain electrode.
11. The method of claim 1 , wherein the step for ashing the first photoresist pattern thus to expose a part of an active region further comprises exposing a part of a high-concentrated impurity layer of the active region by oxidizing a part of the photoresist with oxygen ion-containing plasma gas.
12. The method of claim 1 , wherein the step for applying a second photoresist pattern as a mask thus to form a pixel region comprises sequentially removing the passivation layer and the active layer formed at the pixel region.
13. The method of claim 12 , wherein the step for applying a second photoresist pattern as a mask thus to form a pixel region further comprises removing the gate insulating layer formed at the pixel region.
14. A method for manufacturing a semiconductor device comprising:
providing a substrate;
forming a photoresist layer over the substrate;
forming a conductive layer over the photoresist layer;
simultaneously removing the photoresist layer and the conductive layer, said conductive layer being removed only at portions corresponding to the photoresist layer to form a source/drain electrode;
forming a passivation layer on the substrate including the source/drain electrode;
forming a second photoresist pattern that exposes a pixel region on the passivation layer;
forming a pixel region by using the second photoresist pattern as a mask;
side-etching a part of the passivation layer thus to expose a part of the drain electrode;
forming a pixel electrode material over the second photoresist pattern and the pixel region; and
simultaneously removing the second photoresist pattern and the pixel electrode material formed thereon to form a pixel electrode.
15. The method of claim 14 , wherein the photoresist is a positive photoresist or a negative photoresist.
16. The method of claim 14 , wherein the conductive layer is formed from a metal or metal oxide.