Solar cell and method of manufacturing therefor

• US 10,727,359 B2
• Filed: 06/12/2014
• Issued: 07/28/2020
• Est. Priority Date: 06/17/2013
• Status: Active Grant

• Current Assignee: Jun Young Kwon
• Original Assignee: Jun Young Kwon
• Inventors: Jun, Young Kwon
• Primary Examiner(s): Golden, Andrew J
• Application Number:
  US14/442,727
• Publication Number:
  US 20150287848A1
• Time in Patent Office: 2,238 Days
• Field of Search: 136243-265
• CPC Class Codes: H01L 31/022425 for solar cells
• CPC Class Codes: H01L 31/0322 comprising only AIBIIICVI chalcopyrite compounds, e.g. Cu In Se2, Cu Ga Se2, Cu In Ga Se2
• CPC Class Codes: H01L 31/0326 comprising AIBIICIVDVI kesterite compounds, e.g. Cu2ZnSnSe4, Cu2ZnSnS4
• CPC Class Codes: H01L 31/06 characterised by potential barriers
• CPC Class Codes: H01L 31/0749 including a AIBIIICVI compound, e.g. CdS/CulnSe2 [CIS] heterojunction solar cells
• CPC Class Codes: H01L 31/075 the potential barriers being only of the PIN type, e.g. amorphous silicon PIN solar cells
• CPC Class Codes: H01L 31/18 Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells
• 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

Abstract

The present invention relates to a structure of a solar cell for improving photoelectric conversion efficiency of the solar cell, and a manufacturing method therefor. One aspect of the solar cell according to the present invention relates to a solar cell having a light-absorbing layer formed between two electrodes arranged to face each other, wherein an electrical polarization layer comprising an electrical polarization material forming an inner electrical field is formed between the electrodes and the light-absorbing layer.

Claims

1. A method of manufacturing a solar cell, comprising:

forming a light-absorbing layer between two electrodes which are disposed to face each other; and

forming an electrical polarization layer having a thickness of 10 nm to 100 nm, which includes an electrical polarization material forming a built-in electric field, on the light-absorbing layer, wherein the solar cell is free from a buffer layer as replaced by the electrical polarization layer,

wherein the electrical polarization layer is formed by a process comprising;

forming a metal oxide layer on one surface of the light-absorbing layer; and

causing a chemical reaction between the light-absorbing layer and the metal oxide layer, the chemical reaction forming the electrical polarization material of the electrical polarization layer,

wherein the metal oxide layer is comprised of a metal oxide having a compound including titanium(Ti) or both of titanium(Ti) and copper(Cu).

2. The method of claim 1, wherein the built-in electric field is increased by applying an electric field to both opposite upper and lower surfaces of the electrical polarization layer.

3. The method of claim 2, wherein the electric field applied to increase the built-in electric field is less than a reverse breakdown voltage of the solar cell.

4. The method of claim 1, wherein the electrical polarization layer is formed by physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or a wet coating method.

5. The method of claim 4, wherein, in a case where the electrical polarization layer is formed by the atomic layer deposition, the electrical polarization layer is formed by a process comprising:

adsorbing one or both of a calcium (Ca) compound precursor material and a copper (Cu) compound precursor material in addition to a titanium (Ti) compound precursor material to the light-absorbing layer; and

forming an adsorption layer of the precursor materials as an oxide by an oxidation reaction.

6. The method of claim 5, wherein the Ca compound precursor material comprises at least one selected from Ca(Thd)₂(Tetraen)[=C₃₀H₆₁CaN₅O₄] and Ca₃(thd)₆ [=Ca₃(C₁₁H₂₀O₂)₆].

7. The method of claim 5, wherein the Cu compound precursor material comprises at least one selected from the group consisting of Cu(hfac)(tmvs)[=C₁₀H₁₃CuF₆O₂Si], Cu(hfac)₂[=Cu(CF₃COCHCOCF₃)₂], (hfac)Cu(DMB)[=Cu(CF₃COCHCOCF₃)[CH₂CHC(CH₃)₃]], and Cu(ethylketoiminate)₂[=Cu(CH₃COCHCN(CH₂CH₃)CH₃)]₂].

8. The method of claim 5, wherein the Ti compound precursor material comprises at least one selected from Ti(O-iPr)₂(DPM)₂[=Ti(C₃H₇O)₂(C₁₁H₁₉O₂)₂] and TiO(thd)₂[=TiO(C₁₁H₂₀O₂)₂].

9. The method of claim 4, wherein the wet coating method comprises at least one selected from the group consisting of chemical bath deposition, spin coating, doctor-blade coating, drop-casting, screen printing, and inkjet printing.

10. The method of claim 4, wherein the wet coating method comprises:

preparing a solution in which a metal oxide is dissolved;

coating the solution; and

performing a heat treatment.

11. The method of claim 10, wherein the metal oxide is a compound including Ti.

12. The method of claim 10, wherein the metal oxide is a compound including Ti and Cu.

13. The method of claim 1, wherein the metal oxide layer is formed by atomic layer deposition using a precursor material including Ti.

14. The method of claim 13, wherein the precursor material including Ti comprises tetrakis(dimethylamino)titanium, tetrakis(diethylamido)titanium, tetrakis(ethylmethylamido)titanium, tetraisopropoxide, or a combination thereof.