Micro/nanostructure PN junction diode array thin-film solar cell and method for fabricating the same

• US 20100055824A1
• Filed: 12/29/2008
• Published: 03/04/2010
• Est. Priority Date: 08/29/2008
• Status: Active Grant

• Current Assignee: National Taiwan University (Government of The Republic of China)
• Original Assignee: National Taiwan University (Government of The Republic of China)
• Inventors: Lin, Ching-Fuh, Chao, Jiun-Jie, Shiu, Shu-Chia
• Granted Patent: US 8,258,396 B2
• Time in Patent Office: Days
• US Class Current: 438/73
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H01L 29/6609 Diodes
• CPC Class Codes: H01L 29/861 Diodes
• CPC Class Codes: H01L 31/03529 Shape of the potential jump barrier or surface barrier
• CPC Class Codes: H01L 31/0384 including other non-monocrystalline materials, e.g. semiconductor particles embedded in an insulating material H01L31/0392 takes precedence
• CPC Class Codes: H01L 31/0392 including thin films deposited on metallic or insulating substrates ; characterised by specific substrate materials or substrate features or by the presence of intermediate layers, e.g. barrier layers, on the substrate textured substrates H01L31/02366
• CPC Class Codes: H01L 31/03926 comprising a flexible substrate
• 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 31/1892 methods involving the use of temporary, removable substrates
• CPC Class Codes: H10K 30/20 comprising organic-organic junctions, e.g. donor-acceptor junctions
• CPC Class Codes: H10K 39/10 Organic photovoltaic [PV] modules; Arrays of single organic PV cells
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02E 10/549 Organic PV cells

Abstract

The present invention discloses a micro/nanostructure PN junction diode array thin-film solar cell and a method for fabricating the same, wherein a microstructure or sub-microstructure PN junction diode array, such as a nanowire array or a nanocolumns array, is transferred from a source-material wafer to two pieces of transparent substrates, which are respectively corresponding to two electric conduction types, to fabricate a thin-film solar cell. In the present invention, the micro/nanostructure PN junction diode array has advantages of a fine-quality crystalline semiconductor, and the semiconductor substrate can be reused to save a lot of semiconductor material. Besides, the present invention can make the best of sunlight energy via stacking up the solar cells made of different types of semiconductor materials to absorb different wavebands of the sunlight spectrum.

Claims

1. A micro/nanostructure PN junction diode array thin-film solar cell comprising

a first transparent substrate;

a thin-film N-type semiconductor joined to said first transparent substrate;

a semiconductor micro/nanostructure array with one side thereof joined to said thin-film N-type semiconductor;

a thin-film P-type semiconductor joined to another side of said semiconductor micro/nanostructure array; and

a second transparent substrate joined to said thin-film P-type semiconductor.

2. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein each of said thin-film N-type semiconductor and said thin-film P-type semiconductor is made of a material selected from a group consisting of silicon, germanium, gallium arsenide, indium phosphide, gallium phosphide, gallium antimonide, zinc telluride, an elemental semiconductor, a binary compound semiconductor, a ternary compound semiconductor, a quaternary compound semiconductor, and a combination of semiconductor materials mentioned above, wherein said semiconductor micro/nanostructure array is made of a material selected from a group consisting of silicon, germanium, gallium arsenide, indium phosphide, gallium phosphide, gallium antimonide, zinc telluride, an elemental semiconductor, a binary compound semiconductor, a ternary compound semiconductor, a quaternary compound semiconductor, and a combination of semiconductor materials mentioned above, wherein each of said first transparent substrate and said second transparent substrate is made of a material selected from a group consisting of a plastic plate, a glass plate, a quartz plate, a plastic plate coated with a transparent conductive film, a glass plate coated with a transparent conductive film, and a quartz plate coated with a transparent conductive film, and wherein said transparent conductive film is made of ITO (Indium Tin Oxide) or FTO (Fluorine-doped Tin Oxide).

3. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein said thin-film N-type semiconductor is made of a small molecule organic semiconductor material selected from a group consisting of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD), aluminum tris(8-hydroxyquinoline) (Alq3), (1-(3-methoxycarbonyl)-propyl-1-1-phenyl-(6,6)C61) (PCBM), 4,4′

-bis(2,2′

diphenyl vinyl)-1,1′

-biphenyl (DPVBi), beryllium-quinoline complex (Beq2), Aluminum(III) bis(2-methyl-8-quinolinate)4-phenylphenolate (Balq), oxadiazole (OXD), or 2,5-bis(tert-butyl-2-benzoxazolyl)thiophene (BBOT) wherein said thin-film P-type semiconductor is made of a small molecule organic semiconductor material selected from a group consisting of poly(3-hexylthiophene) (P3HT), poly[2-methoxy-5-(2′

-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV), poly[2-metoxy-5-(3′

,7′

-dimethyloctyloxy)-p-phenylene vinylene] (MDMO-PPV), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(9,9-dioctylfluoreny-2,7-diyl) (PFO), (N,N′

-diphenyl-N,N′

-bis(3-methyl-phenyl)-1,1′

-biphenyl-4,4′

diamine) (TPD), or N,N′

-his-(1-naphthyl)-N,N′

-diphenyl-1,1′

-biphenyl-4,4′

-diamine (NPB).

4. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein a longitudinal section of said semiconductor micro/nanostructure array has a width of from 1 nm to 3000 μ

m, wherein a longitudinal section of said semiconductor micro/nanostructure array has a length of from 50 nm to 50 μ

m.

5. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein said semiconductor micro/nanostructure array is made of a P-type semiconductor material or an N-type semiconductor material.

6. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein said semiconductor micro/nanostructure array is made of an N-type semiconductor material.

7. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein said semiconductor micro/nanostructure array is an array of diodes each having at least one PN junction;

outmost P-type portions of said diodes are joined to said thin-film P-type semiconductor, and outmost N-type portions of said diodes are joined to said thin-film N-type semiconductor, wherein said semiconductor micro/nanostructure array is an array of diodes each having a plurality of PN junctions and absorbing different wavebands of sunlight.

8. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1 further comprises another said micro/nanostructure PN junction diode array thin-film solar cell stacked thereabove to form a stack structure, wherein said semiconductor micro/nanostructure array of each said micro/nanostructure PN junction diode array thin-film solar cell absorbs a different waveband of sunlight.

9. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein a transparent non-conductive material is filled into gaps of said semiconductor micro/nanostructure array.

10. The micro/nanostructure PN junction diode array thin-film solar cell according to claim 1, wherein a thin metal layer is formed in between said first transparent substrate and said thin-film N-type semiconductor- or in between said second transparent substrate and said thin-film P-type semiconductor, wherein a vacuum process is used to form said thin metal layer, and temperature used by said vacuum process depends on a heat-resistant capability of said first transparent substrate or said second transparent substrate;

wherein said thin metal layer is made of a metallic material having an appropriate work function with respect to energy levels of said semiconductor micro/nanostructure array.

11. A method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell comprising steps:

providing a source-material wafer having a semiconductor micro/nanostructure array;

coating a thin-film N-type semiconductor on a first transparent substrate;

making said semiconductor micro/nanostructure array contact said thin-film N-type semiconductor of said first transparent substrate;

fusing together said thin-film N-type semiconductor and one side of said semiconductor micro/nanostructure array;

detaching said semiconductor micro/nanostructure array and transferring said semiconductor micro/nanostructure array to said first transparent substrate;

coating a thin-film P-type semiconductor on a second transparent substrate;

making said semiconductor micro/nanostructure array contact said thin-film P-type semiconductor of said second transparent substrate; and

fusing together said thin-film P-type semiconductor and another side of said semiconductor micro/nanostructure array to form said micro/nanostructure PN junction diode array thin-film solar cell.

12. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein said step of “

fusing together said thin-film N-type semiconductor and one side of said semiconductor micro/nanostructure array”

or said step of “

fusing together said thin-film P-type semiconductor and another side of said semiconductor micro/nanostructure array”

is realized with laser illumination or with heating and pressing.

13. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein each of said thin-film N-type semiconductor and said thin-film P-type semiconductor is made of a material selected from a group consisting of silicon, germanium, gallium arsenide, indium phosphide, gallium phosphide, gallium antimonide, zinc telluride, an elemental semiconductor, a binary compound semiconductor, a ternary compound semiconductor, a quaternary compound semiconductor, and a combination of semiconductor materials mentioned above, wherein said semiconductor micro/nanostructure array is made of a material selected from a group consisting of silicon, germanium, gallium arsenide, indium phosphide, gallium phosphide, gallium antimonide, zinc telluride, an elemental semiconductor, a binary compound semiconductor, a ternary compound semiconductor, a quaternary compound semiconductor, and a combination of semiconductor materials mentioned above, wherein each of said first transparent substrate and said second transparent substrate is made of a material selected from a group consisting of a plastic plate, a glass plate, a quartz plate, a plastic plate coated with a transparent conductive film, a glass plate coated with a transparent conductive film, and a quartz plate coated with a transparent conductive film, wherein said transparent conductive film is made of ITO (Indium Tin Oxide) or FTO (Fluorine-doped Tin Oxide), and wherein said source-material wafer is made of a material selected from a group consisting of silicon, germanium, gallium arsenide, indium phosphide, gallium phosphide, gallium antimonide, zinc telluride, an elemental semiconductor, a binary compound semiconductor, a ternary compound semiconductor, a quaternary compound semiconductor, and a combination of semiconductor materials mentioned above.

14. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein said thin-film N-type semiconductor is made of a small molecule organic semiconductor material selected from a group consisting of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD), aluminum tris(8-hydroxyquinoline) (Alq3), (1-(3-methoxycarbonyl)-propyl-1-1-phenyl-(6,6)C61) (PCBM), 4,4′

-bis(2,2′

diphenyl vinyl)-1,1′

-biphenyl (DPVBi), beryllium-quinoline complex (Beq2), Aluminum(III) bis(2-methyl-8-quinolinate)4-phenylphenolate (Balq), oxadiazole (OXD), or 2,5-bis(tert-butyl-2-benzoxazolyl)thiophene (BBOT), wherein said thin-film P-type semiconductor is made of a small molecule organic semiconductor material selected from a group consisting of poly(3-hexylthiophene) (P3HT), poly[2-methoxy-5-(2′

-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV), poly[2-metoxy-5-(3′

,7′

-dimethyloctyloxy)-p-phenylene vinylene] (MDMO-PPV), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(9,9-dioctylfluoreny-2,7-diyl) (PFO), (N,N′

-diphenyl-N,N′

-bis(3-methyl-phenyl)-1,1′

-biphenyl-4,4′

diamine) (TPD), or N,N′

-his-(1-naphthyl)-N,N′

-diphenyl-1,1′

-biphenyl-4,4′

-diamine (NPB).

15. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein said semiconductor micro/nanostructure array is formed with an epitaxial method, a doping method, an etching method, or a crystal growth method, wherein said etching method is a dry etching method, a wet etching method, a physical etching method, a chemical etching method, or a combination thereof, and wherein a mask used by said etching method is a photoresist patterned with a photolithographic technology, spin-coated nanoparticles, nanoislands formed via rapidly annealing a coated metal film, a template fabricated with an AAO (Anodic Aluminum Oxide) method, a template fabricated with an electrochemical CVD (Chemical Vapor Deposition) method.

16. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11 further comprising steps:

coating a curable adhesive on a temporary substrate, wherein said temporary substrate is made of a semiconductor material, a conductive material, or an insulating material, which said curable adhesive can be applied onto;

inserting said semiconductor micro/nanostructure array of said source-material wafer into said curable adhesive of said temporary template;

curing said curable adhesive, wherein said curable adhesive is a sol, a gel glue, a melted metal, a polymer, an SOG (Spin-On-Glass), a wax, PMMA (polymethylmethacrylate), or P3HT; and

separating said semiconductor micro/nanostructure array from said source-material wafer and transferring said semiconductor micro/nanostructure array to said temporary substrate, wherein said semiconductor micro/nanostructure array is separated from said source-material wafer via ultrasonic vibration, slight knocking, chemical etching, or directly lifting said source-material wafer, wherein said semiconductor micro/nanostructure array is detached from said temporary substrate with sticking force, stress, chemical etching, or laser melting, or via dissolving said curable adhesive with a solvent.

17. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein a selectively-etched layer is formed in between said source-material wafer and said semiconductor micro/nanostructure array before said semiconductor micro/nanostructure array is fabricated with an epitaxial process and an etching method, wherein said semiconductor micro/nanostructure array is separated from said source-material wafer via removing said selectively-etched layer with a chemical etching method or a dry etching method.

18. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein a longitudinal section of said semiconductor micro/nanostructure array has a width of from 1 nm to 3000 μ

m.

19. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein said semiconductor micro/nanostructure array is made of a P-type semiconductor material or an N-type semiconductor material.

20. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11, wherein said semiconductor micro/nanostructure array is an array of diodes each having at least one PN junction;

outmost P-type portions of said diodes are joined to said thin-film P-type semiconductor, and outmost N-type portions of said diodes are joined to said thin-film N-type semiconductor, wherein said semiconductor micro/nanostructure array is an array of diodes each having a plurality of PN junctions and absorbing different wavebands of sunlight.

21. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11 further comprising a step:

stacking another said micro/nanostructure PN junction diode array thin-film solar cell to form a stack structure; and

wherein said semiconductor micro/nanostructure array of each said micro/nanostructure PN junction diode array thin-film solar cell absorbs a different waveband of sunlight.

22. The method for fabricating a micro/nanostructure PN junction diode array thin-film solar cell according to claim 11 further comprising a step:

filling a transparent non-conductive material into gaps of said semiconductor micro/nanostructure array.