Photoelectric device and manufacturing method thereof

1. A photoelectric device, comprising:

a semiconductor substrate;

first and second semiconductor stacks having opposite conductive types, the first and second semiconductor stacks alternately arranged on a first surface of the semiconductor substrate;

a gap insulation layer formed between the first and second semiconductor stacks;

an undercut formed in the gap insulation layer; and

end portions of the first and second semiconductor stacks formed covering a side surface and at least part of an upper surface of the gap insulation layer.

2. The photoelectric device of claim 1 , wherein the gap insulation layer comprises a bottom surface facing the first surface of the semiconductor substrate and left and right side surfaces, and wherein the undercut is formed in at least one of the left and the right side surfaces.

3. The photoelectric device of claim 1 further comprising a capping layer formed on a second surface of the semiconductor substrate, the second surface formed opposing and substantially parallel to the first surface.

4. The photoelectric device of claim 3 , wherein the capping layer comprises an insulation layer.

5. The photoelectric device of claim 4 , wherein the capping layer is formed of at least one of a silicon oxide layer and a silicon nitride layer.

6. The photoelectric device of claim 3 , wherein the capping layer is formed on a textured structure formed on the second surface of the semiconductor substrate.

7. The photoelectric device of claim 1 , wherein the first semiconductor stack comprises:

a first intrinsic semiconductor layer formed on the first surface of the semiconductor substrate;

a first conductive semiconductor layer formed on the first intrinsic semiconductor layer; and

a first transparent conductive layer formed on the first conductive semiconductor layer.

8. The photoelectric device of claim 1 , wherein the second semiconductor stack comprises:

a second intrinsic semiconductor layer formed on the first surface of the semiconductor substrate;

a second conductive semiconductor layer formed on the second intrinsic semiconductor layer; and

a second transparent conductive layer formed on the second conductive semiconductor layer.

9. A method of manufacturing a photoelectric device, the method comprising:

preparing a semiconductor substrate having first and second surfaces opposing each other;

forming a capping layer on the second surface of the semiconductor substrate;

forming a first semiconductor stack material layer on the first surface of the semiconductor substrate;

patterning the first semiconductor stack material layer by wet etching to form a first semiconductor stack;

forming a second semiconductor stack material layer on the first surface of the semiconductor substrate where the first semiconductor stack is formed;

patterning the second semiconductor stack material layer by wet etching to form a second semiconductor stack;

forming a gap insulation layer on the first surface of the semiconductor substrate; and

forming end portions of the first and second semiconductor stacks to cover a side surface and at least part of an upper surface of the gap insulation layer.

10. The method of claim 9 , wherein the forming the capping layer is performed before the forming the first semiconductor stack.

11. The method of claim 9 , wherein the first semiconductor stack material layer comprises a first conductive semiconductor layer doped to have p-type conductivity.

12. The method of claim 9 , wherein the capping layer comprises an insulation layer.

13. The method of claim 9 , wherein the wet etching comprises an etching solution including a combination of hydrofluoric acid (HF), nitric acid (HNO3), and pure water (DI water) or an etching solution of a combination of hydrofluoric acid (HF), nitric acid (HNO3), and acetic acid (CH3COOH).

14. The method of claim 9 , wherein the first and second semiconductor stacks are respectively formed on non-overlapping areas of the first and second semiconductors.