Structure, chemistry, and growth mechanisms of photovoltaic quality thin-film Cu(In,Ga)Se[sub 2] grown from a mixed-phase precursor

Journal Article · Sun Jan 01 00:00:00 EST 1995 · Journal of Applied Physics; (United States)

DOI:https://doi.org/10.1063/1.359362· OSTI ID:6720854

Tuttle, J R; Contreras, M; Bode, M H; Niles, D; Albin, D S; Matson, R; Gabor, A M; Tennant, A; Duda, A; Noufi, R ^[1]

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1. National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, Colorado 80401 (United States)

The formation chemistry and growth dynamics of thin-film CuInSe[sub 2] grown by physical vapor deposition have been considered along the reaction path leading from the Cu[sub [ital x]]Se:CuInSe[sub 2] two-phase region to single-phase CuInSe[sub 2]. The (Cu[sub 2]Se)[sub [beta]](CuInSe[sub 2])[sub 1[minus][beta]] (0[lt][beta][le]1) mixed-phase precursor is created in a manner consistent with a liquid-phase assisted growth process. At substrate temperatures above 500 [degree]C and in the presence of excess Se, the film structure is columnar through the film thickness with column diameters in the range of 2.0--5.0 [mu]m. Films deposited on glass are described as highly oriented with nearly exclusive (112) crystalline orientation. CuInSe[sub 2]:Cu[sub [ital x]]Se phase separation is identified and occurs primarily normal to the substrate plane at free surfaces. Single-phase CuInSe[sub 2] is created by the conversion of the Cu[sub [ital x]]Se into CuInSe[sub 2] upon exposure to In and Se activity. Noninterrupted columnar growth continues at substrate temperatures above 500 [degree]C. The addition of In in excess of that required for conversion produces an In-rich near-surface region with a CuIn[sub 3]Se[sub 5] surface chemistry. A model is developed that describes the growth process. The model provides a vision for the production of thin-film CuInSe[sub 2] in industrial scale systems. Photovoltaic devices incorporating Ga with total-area efficiencies of 14.4%--16.4% have been produced by this process and variations on this process.

• DOE Contract Number: AC36-83CH10093
• OSTI ID: 6720854
• Journal Information: Journal of Applied Physics; (United States), Vol. 77:1; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
COPPER SELENIDES
PHOTOVOLTAIC EFFECT
GALLIUM SELENIDES
INDIUM SELENIDES
CRYSTAL STRUCTURE
GROWTH
PHASE STUDIES
PHYSICAL VAPOR DEPOSITION
POLYCRYSTALS
PRECURSOR
SOLAR CELLS
THIN FILMS
CHALCOGENIDES
COPPER COMPOUNDS
CRYSTALS
DEPOSITION
DIRECT ENERGY CONVERTERS
EQUIPMENT
FILMS
GALLIUM COMPOUNDS
INDIUM COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
SELENIDES
SELENIUM COMPOUNDS
SOLAR EQUIPMENT
SURFACE COATING
TRANSITION ELEMENT COMPOUNDS
140501* - Solar Energy Conversion- Photovoltaic Conversion
360606 - Other Materials- Physical Properties- (1992-)