Light-emitting or light-receiving semiconductor device and method for fabricating the same

• US 6,744,073 B1
• Filed: 06/20/2002
• Issued: 06/01/2004
• Est. Priority Date: 10/20/2000
• Status: Expired due to Term

• Current Assignee: Sphelar Power Corporation (Dexerials Corporation)
• Original Assignee: Josuke Nakata
• Inventors: Nakata, Josuke
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): HO, TU TU V
• Application Number:
  US10/168,810
• Time in Patent Office: 712 Days
• Field of Search: 257/81, 257/82, 257/88, 257/91, 257/99, 257/459, 257/79
• US Class Current: 257/81
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 31/02168 the coatings being antireflective or having enhancing optical properties for the solar cells
• CPC Class Codes: H01L 31/035281 Shape of the body
• CPC Class Codes: H01L 31/03529 Shape of the potential jump barrier or surface barrier
• CPC Class Codes: H01L 31/042 PV modules or arrays of single PV cells supporting structures for PV modules H02S20/00
• CPC Class Codes: H01L 31/068 the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells

Abstract

A semiconductor device (10) having light-receiving functions can include, for example: a semiconductor element (1) formed from a p-type silicon single crystal: first and second flat surfaces (2, 7); a n-type diffusion layer (3) and a pn junction (4) thereof; a recrystallized layer (8); a reflection prevention film (6a); a negative electrode (9a) and a positive electrode (9b). A cylindrical semiconductor element can be used in place of the semiconductor element (1).

Claims

1. A light-emitting or light-receiving semiconductor device comprising:

a roughly spherical semiconductor element formed from one of a p-type and a n-type semiconductor, said semiconductor element being formed with parallel first and second flat surfaces at ends on either side of a center thereof;

a diffusion layer formed on a surface section of said semiconductor element including said first flat surface;

a roughly spherical pn junction formed on said diffusion layer; and

first and second electrodes disposed on said first and said second flat surfaces respectively and connected to ends of said pn junction.

2. A light-emitting or light-receiving semiconductor device, according to claim 1, wherein an average diameter of said first and said second flat surfaces is smaller than a distance between said flat surfaces.

3. A light-emitting or light-receiving semiconductor device, according to claim 1, wherein said first and said second flat surfaces are formed with different diameters.

4. A light-emitting or light-receiving semiconductor device, according to claim 2, wherein said semiconductor element is made from a spherical semiconductor element.

5. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein said semiconductor element is a single crystal semiconductor.

6. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein said semiconductor element is a silicon semiconductor.

7. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein said semiconductor element is a mixed-crystal silicon and germanium semiconductor.

8. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein said semiconductor element is a compound semiconductor formed from at least one of a group consisting of GaAs, InP, GaP, GaN, and InCuSe.

9. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein:

said semiconductor element is formed from a p-type semiconductor;

said diffusion layer is formed from an n-type diffusion layer;

a p-type diffusion layer is formed on said second flat surface; and

a said second electrode is disposed on a surface of said p-type diffusion layer.

10. A light-emitting or light-receiving semiconductor device as described in claim 2 wherein:

said semiconductor element is formed from an n-type semiconductor;

said diffusion layer is formed from a p-type diffusion layer;

an n-type diffusion layer is formed on said second flat surface; and

said second electrode is disposed on a surface of said n-type diffusion layer.

11. A light-emitting or light-receiving semiconductor device comprising:

a cylindrical semiconductor element formed from one of a p-type and n-type semiconductor, said semiconductor element being formed with parallel first and second flat surfaces at ends of said element and perpendicular to an axis thereof;

a diffusion layer formed on a surface section of said semiconductor element including said first flat surface;

a roughly cylindrical pn junction formed on said diffusion layer; and

first and second electrodes disposed on said first and said second flat surfaces respectively and connected to ends of said pn junction.

12. A light-emitting or light-receiving semiconductor device, according to claim 11, wherein an average diameter of said first and said second flat surfaces is smaller than a distance between said flat surfaces.

13. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein said semiconductor element is a single crystal semiconductor.

14. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein said semiconductor element is a silicon semiconductor.

15. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein said semiconductor element is a mixed-crystal silicon and germanium semiconductor.

16. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein said semiconductor element is a compound semiconductor formed from at least one of a group consisting of GaAs, InP, GaP, GaN, and InCuSe.

17. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein:

said semiconductor element is formed from a p-type semiconductor;

said diffusion layer is formed from a n-type diffusion layer;

a p-type diffusion layer is formed on said second flat surface; and

a second electrode is disposed on a surface of said p-type diffusion layer.

18. A light-emitting or light-receiving semiconductor device as described in claim 12 wherein:

said semiconductor element is formed from a n-type semiconductor;

said diffusion layer is formed from a p-type diffusion layer;

a n-type diffusion layer is formed on said second flat surface; and

a second electrode is disposed on a surface of said n-type diffusion layer.

19. A method for making a light emitting or light-receiving semiconductor device comprising:

a first step for making a spherical semiconductor element formed from one of a p-type and n-type semiconductor;

a second step for forming a first flat surface at an end of said semiconductor element;

a third step for forming on a surface section of said semiconductor element including said first flat surface a diffusion layer from a conductor different from said semiconductor element and a roughly spherical pn junction on said diffusion layer;

a fourth step for forming a second flat surface by removing said diffusion layer, said flat surface being parallel to said first flat surface and positioned opposite from said first flat surface of said semiconductor element; and

a fifth step for forming a first and a second electrode on said first and said second flat surface respectively, said first and said second electrodes being connected to ends of said pn junction.

20. A method for making a light emitting or light-receiving semiconductor device comprising:

a first step for making a spherical semiconductor element formed from a p-type semiconductor;

a second step for forming parallel first and second flat surfaces on either end of a center of said semiconductor element;

a third step for forming on a surface section of said semiconductor element including said first flat surface and said second flat surface a n-type diffusion layer and a roughly spherical pn junction on said diffusion layer; and

a fourth step for forming a first and a second electrode on said first and said second flat surface respectively, said first and said second electrodes being connected to ends of said pn junction.

21. A method for making a light emitting or light-receiving semiconductor device as described in claim 20, wherein in said fourth step, a small piece of at least one of a group consisting of Al, AuGa, and AuB is placed in contact with said second flat surface and heated and fused to form a p-type recrystallized layer passing through said diffusion layer and a second electrode continuous with said recrystallized layer.

22. A method for making a light emitting or light-receiving semiconductor device comprising:

a first step for making a cylindrical semiconductor element formed from at least one of a p-type and n-type semiconductor and forming parallel first and second flat surfaces at ends of said semiconductor element, said surfaces being perpendicular to an axis thereof;

a second step for forming on a surface section of said semiconductor element including said first flat surface a diffusion layer from a conductor different from said semiconductor element and a pn junction on said diffusion layer; and

a third step for forming a first and a second electrode on said first and said second flat surface respectively, said first and said second electrodes being connected to ends of said pn junction.

23. A method for making a light emitting or light-receiving semiconductor device as described in claim 22 wherein in said third step, a small piece of at least one of a group consisting of Al, AuGa, and AuB is placed in contact with said second flat surface and heated and fused to form one of a p-type and an n-type recrystallized layer passing through said diffusion layer and a second electrode continuous with said recrystallized layer.

24. A light emitting or light receiving semiconductor device comprising:

a semiconductor element formed from one of a p-type and a n-type semiconductor, said semiconductor element being formed with parallel first and second flat surfaces at ends on either side of a center thereof;

said semiconductor element having a shape selected from the group comprising roughly spherical and cylindrical;

a diffusion layer formed on a surface section of said semiconductor element including said first flat surface;

a pn junction formed with said diffusion layer; and

first and second electrodes disposed on said first and said second flat surfaces respectively and connected to ends of said pn junction.

25. A method for making a light emitting or light receiving semiconductor device comprising:

a first step for making a semiconductor element formed from one of a p-type and n-type semiconductor, said semiconductor element having a shape selected from the group comprising roughly spherical and cylindrical;

a second step for forming a first flat surface at an end of said semiconductor element;

a third step for forming on a surface section of said semiconductor element including said first flat surface a diffusion layer from a conductor different from said semiconductor element and a pn junction formed with said diffusion layer;

a fourth step for forming a second flat surface by removing said diffusion layer, said second flat surface being parallel to said first flat surface and positioned opposite from said first flat surface of said semiconductor element; and

a fifth step for forming a first and a second electrode on said first and said second flat surface respectively, said first and said second electrodes being connected to end of said pn junction.