Thin film solar cell and method of fabricating the same
a technology solar cells, which is applied in the direction of sustainable manufacturing/processing, final product manufacturing, vacuum evaporation coating, etc., can solve the problems of low efficiency of thin film solar cells, high material cost of indium (in), and grain boundary defects, etc., to achieve excellent current-voltage characteristics, light conversion efficiency, and suppress grain boundary defects
Patent Information
- Authority / Receiving Office
- US · United States
- Patent Type
- Applications(United States)
- Current Assignee / Owner
- Publication Date
- 2015-04-30
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
Figure 1 Figure 2 Figure 3
Abstract
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a thin film solar cell and a method for manufacturing the same, and more particularly, to a method for manufacturing a thin film solar cell having improved light conversion efficiency through a heat treatment process of a first electrode.
[0003] 2. Description of the Prior Art
[0004] Chalcopyrite-based solar cell technology is highly likely to ensure high efficiency in all thin film solar cell technologies. CuInSe2, CuInS2, Cu(In,Ga)Se2, or the like, is used for the thin film solar cell. However, the solar cell having this composition has difficulty in realizing a low priced thin film solar cell since the reserve of indium (In) is restricted and the material cost of indium (In) is expensive.
[0005] A thin film solar cell having a light absorbing layer of CZTS(Cu2ZnSn(S,Se)4) has been suggested as an alternative to solve the problem. The CZTS-based solar cell enables the realization of low-pric...
Examples
example 1
[0065]A soda lime glass substrate (100) was prepared, and a first electrode (200) of molybdenum (Mo) was deposited to have a thickness of about 0.5 μm on the substrate (100) through DC sputtering.
[0066]The first electrode was heat-treated at 400° C. for 10 minutes under nitrogen atmosphere.
example 2
[0067]A first electrode was formed by the same method as in example 1 except that the first electrode was heat-treated at 600° C.
manufacture examples 1 to 4
[0072]A CZT-based metallic precursor layer was formed by sputter-depositing a Zn precursor (301), a Sn precursor (302), and a Cu precursor (303) on each of the first electrodes (200) formed in examples 1 and 2 and comparative examples in the order shown in FIG. 5.
[0073]After that, the CZT-based metallic precursor layer was heat-treated according to a sulfurizing process. The heat treatment was conducted in a furnace including a first furnace and a second furnace. A sulfur (S) powder was heated at 300° C. in the first furnace, and the first electrode formed in example 1 was put in the second furnace, followed by a sulfurization treatment at a temperature of 600° C. As a result, as shown in FIG. 6, a CZTS-based light absorbing layer (300) was formed.
[0074]Then, a CdS buffer layer (400) of 60 nm, a ZnO window layer (500) of 400 nm, and an Al electrode (600) were formed on the CZTS-based light absorbing layer, thereby completing a CZTS-based thin film solar cell.
[0075](Photographing of ...