Method of making a semiconductor photoelectric conversion device having a crystalline I-type layer

• US 5,478,777 A
• Filed: 09/22/1994
• Issued: 12/26/1995
• Est. Priority Date: 05/15/1984
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US08/310,375
• Time in Patent Office: 460 Days
• Field of Search: 437/4, 437/173-174, 437/233, 437/942, 437/967, 136/258 PC
• US Class Current: 438/487
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/022475 composed of indium tin oxide [ITO]
• CPC Class Codes: H01L 31/076 Multiple junction or tandem solar cells
• CPC Class Codes: H01L 31/1864 Annealing
• CPC Class Codes: Y02E 10/548 Amorphous silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 148/004 Annealing, incoherent light
• CPC Class Codes: Y10S 148/154 Solid phase epitaxy
• CPC Class Codes: Y10S 438/931 Silicon carbide semiconductor

Abstract

A method for forming a semiconductor material involves forming an i-type non-single crystalline layer on a substrate and crystallizing the semiconductor material by irradiation with a light having a wavelength in the range of 250 to 600 nm. Desirably, the crystals of the semiconductor material extend in column form approximately perpendicular to the substrate. Preferably, the i-type layer is doped with a recombination center neutralizer selected from hydrogen and a halogen element and the concentration of impurities forming recombination centers, such as oxygen, nitrogen, carbon, phosphorus and boron, are maintained at 1 atomic % or less.

Claims

1. A method for forming a semiconductor material comprising the steps of:

forming an i-type non-single crystalline semiconductor layer; and

crystallizing said semiconductor material by irradiating said semiconductor material with a light having a wavelength in the range of 250 to 600 nm,

where a total concentration of an impurity which forms a recombination center in said semiconductor material is 1 atomic % or less.

2. The method of claim 1 wherein said impurity comprises an element selected from the group consisting of oxygen, nitrogen, carbon, phosphorus, and boron.

3. The method of claim 1 further comprising the step of doping said semiconductor material with a recombination center neutralizer selected from the group consisting of hydrogen and a halogen element.

4. The method of claim 3 wherein said recombination center neutralizer is doped at a concentration in the range of 10 to 20 atomic %.

5. The method of claim 1 wherein said i-type non-single crystalline semiconductor material comprises silicon.

6. The method of claim 1 wherein said i-type non-single crystalline semiconductor material is formed by a plasma CVD.

7. The method of claim 1 wherein said i-type non-single crystalline semiconductor material is formed by a photo CVD.

8. A method for forming a semiconductor material comprising the steps of:

forming an i-type non-single crystalline semiconductor layer on a substrate; and

crystallizing said semiconductor material by irradiating said semiconductor material with a light having a wavelength in the range of 250 to 600 nm,

where crystals of said semiconductor material extend in a column form approximately perpendicular to said substrate.

9. The method of claim 8 filter comprising the step of doping said semiconductor material with a recombination center neutralizer selected from the group consisting of hydrogen and a halogen element.

10. The method of claim 9 wherein said recombination center neutralizer is doped at a concentration in the range of 10 to 20 atomic %.

11. The method of claim 8 wherein said i-type non-single crystalline semiconductor material comprises silicon.

12. The method of claim 8 wherein said i-type non-single crystalline semiconductor material is formed by a plasma CVD.

13. The method of claim 8 wherein said i-type non-single crystalline semiconductor material is formed by a photo CVD.

14. The method of claim 8 wherein said substrate is maintained at a temperature not higher than 400°

C. during said crystallizing.

15. A method for forming a semiconductor material comprising the steps of:

preparing a transparent substrate;

forming an i-type non-single crystalline semiconductor layer on said substrate; and

crystallizing said semiconductor material by irradiating said semiconductor material with a light having a wavelength in the range of 250 to 600 nm,

wherein said light is irradiated from a side of said substrate opposite to said semiconductor material.

16. The method of claim 15 further comprising the step of doping said semiconductor material with a recombination center neutralizer selected from the group consisting of hydrogen and a halogen element.

17. The method of claim 16 wherein said recombination center neutralizer is doped at a concentration in the range of 10 to 20 atomic %.

18. The method of claim 15 wherein said i-type non-single crystalline semiconductor material comprises silicon.

19. The method of claim 15 wherein said i-type non-single crystalline semiconductor material is formed by a plasma CVD.

20. The method of claim 15 wherein said i-type non-single crystalline semiconductor material is formed by a photo CVD.