Array substrate structure and contact structure

1. A contact structure comprising:

a substrate;

an active layer over the substrate;

an insulating layer over the active layer;

an inter-layer dielectric (ILD) layer over the insulating layer;

a contact opening penetrating a portion of the ILD layer and the insulating layer, exposing a portion of the active layer, wherein the contact opening comprises a first recess portion, wherein the first recess portion is defined by a surface of the ILD layer, a sidewall of the insulating layer, and a top surface of the active layer, and wherein the surface of the ILD layer makes an angle with the sidewall of the insulating layer which is not equal to 180 degrees; and

a conductive layer in the contact opening, electrically connected to the active layer.

2. The contact structure as claimed in claim 1 , further comprising a buffer layer disposed between the substrate and the active layer, wherein the contact opening further penetrates a portion of the active layer and the buffer layer to expose a portion of the active layer, the buffer layer, and the substrate, wherein the contact opening further comprises a second recess portion, and the second recess portion is defined by a bottom surface of the active layer, a sidewall of the buffer layer, and a top surface of the substrate, and the conductive layer is disposed over the portion of the buffer layer exposed by the contact opening and the portion of the substrate exposed by the contact opening.

3. The contact structure as claimed in claim 2 , wherein a distance between the sidewall of the insulating layer and the sidewall of the active layer exposed by the contact opening is a first distance, and a distance between the sidewall of the buffer layer and the sidewall of the active layer exposed by the contact opening is a second distance, and the first distance is greater than the second distance.

4. The contact structure as claimed in claim 3 , wherein the first distance is about 0.05-0.5 μm, and the second distance is about 0.01-0.5 μm.

5. The contact structure as claimed in claim 1 , wherein the active layer comprises semiconductor materials.

6. The contact structure as claimed in claim 1 , wherein the angle is less than 180 degrees.

7. An array substrate structure comprising:

a substrate;

an active layer over a portion of the substrate;

an insulating layer over the active layer;

a first conductive layer over the insulating layer, being disposed over a portion of the active layer;

an inter-layer dielectric (ILD) layer over the first conductive layer and the insulating layer;

a contact opening penetrating a portion of the ILD layer and the insulating layer, exposing a portion of the active layer, wherein the contact opening comprises a first recess portion, wherein the first recess portion is defined by a surface of the ILD layer, a sidewall of the insulating layer and a top surface of the active layer, and wherein the sidewall of the ILD layer makes an angle with the sidewall of the insulating layer which is not equal to 180 degrees; and

a second conductive layer in the contact opening, electrically connected to the active layer.

8. The array substrate structure as claimed in claim 7 , further comprising a buffer layer disposed between the substrate and the active layer, wherein the contact opening further penetrates a portion of the active layer and the buffer layer to expose a portion of the active layer, the buffer layer, and the substrate, wherein the contact opening further comprises a second recess portion, and the second recess portion is defined by a bottom surface of the active layer, a sidewall of the buffer layer, and a top surface of the substrate, and the second conductive layer is disposed over the portion of the buffer layer exposed by the contact opening and the portion of the substrate exposed by the contact opening.

9. The array substrate structure as claimed in claim 8 , wherein a distance between the sidewall of the insulating layer and the sidewall of the active layer exposed by the contact opening is a first distance, and a distance between the sidewall of the buffer layer and the sidewall of the active layer exposed by the contact opening is a second distance, and the first distance is greater than the second distance.

10. The array substrate structure as claimed in claim 9 , wherein the first distance is about 0.05-0.5 μm, and the second distance is about 0.01-0.5 μm.

11. The array substrate structure as claimed in claim 7 , wherein the active layer comprises semiconductor materials.

12. The array substrate structure as claimed in claim 8 , wherein the angle is less than 180 degrees.