High-efficiency CuInSe2 solar cells prepared by the two-stage process

The two-step process including the deposition of the metal precursors followed by heating the metal precursors in a vacuum environment of Se overpressure was employed for the preparation of Cu(In,Ga)Se2 (CIGS) films. The CIGS films selenized at the relatively high Se flow rate of 25 Å/s exhibited improved surface morphologies. The correlations among the two-step process parameters, film properties, and cell performance were studied. With the given selenization conditions, the efficiency of 12.5% for the fabricated CIGS solar cells was achieved. The features of co-evaporation processes including the single-stage, bi-layer, and three-stage process were discussed. The characteristics of the co-evaporated CIGS solar cells were presented. Not only the surface morphologies but also the grading bandgap structures were crucial to the improvement of the open-circuit voltage of the CIGS solar cells. Efficiencies of over 17% for the co-evaporated CIGS solar cells have been achieved. Furthermore, the critical factors and the mechanisms governing the performance of the CIGS solar cells were addressed.

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Characterization of Cu(In,Ga)Se2/Mo Interface in CIGS Solar Cells

MRS Proceedings ◽

10.1557/proc-485-139 ◽

1997 ◽

Vol 485 ◽

Cited By ~ 8

Author(s):

S. Nishiwaki ◽

N. Kohara ◽

T. Negami ◽

M. Nishitani ◽

T. Wada

Keyword(s):

Solar Cells ◽

High Efficiency ◽

Soda Lime ◽

Film Deposition ◽

Soda Lime Glass ◽

X Ray Diffraction ◽

Transmission Electron ◽

Current Voltage ◽

Stage Process ◽

Cigs Solar Cells

AbstractThe interface between a Cu(In,Ga)Se2 (CIGS) and an underlying Mo layer was studied by X-ray diffraction and high resolution transmission electron microscopy. The CIGS layer was deposited onto Mo coated soda-lime glass using the “3-stage” process. A MoSe2 layer found to form at the CIGS/Mo interface during the 2nd stage of the “3-stage” process. The thickness of the MoSe2 layer depended on the substrate temperature used for CIGS film deposition as well as the Na content of the CIGS and/or Mo layers. For higher substrate temperatures, thicker MoSe2 layers were observed. The Na in the CIGS and/or Mo layer is felt to assist in the formation of MoSe2. Current-Voltage measurements of the heterojunction formed by the CIGS/Mo interface were ohmic even at low temperature. The role of the MoSe2 layer in high efficiency CIGS solar cells is discussed.

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Thin film solar cells based on CuInS2 films through a two-stage process of sputtering and H2S annealing

Solar Energy Materials and Solar Cells ◽

10.1016/0927-0248(94)90146-5 ◽

1994 ◽

Vol 35 ◽

pp. 239-245 ◽

Cited By ~ 16

Author(s):

T. Watanabe ◽

M. Matsui ◽

K. Mori

Keyword(s):

Thin Film ◽

Solar Cells ◽

Thin Film Solar Cells ◽

Two Stage ◽

Stage Process

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Solar Grade CuInS2 Thin Films Grown at 250°C

MRS Proceedings ◽

10.1557/proc-1165-m08-22 ◽

2009 ◽

Vol 1165 ◽

Author(s):

Thomas Painchaud ◽

Nicolas Barreau ◽

John Kessler

Keyword(s):

Thin Films ◽

Solar Cells ◽

Spinel Structure ◽

High Efficiency ◽

Energy Conversion Efficiency ◽

Chalcopyrite Structure ◽

High Efficiency Solar Cells ◽

Cuins2 Thin Films ◽

Stage Process ◽

Precursor Layer

AbstractCuInS2 (chalcopyrite structure) thin films were synthesized at 250°C using a two-stage process consisting firstly in the co-evaporation of a large grain In2S3 (defect spinel structure) precursor layer followed by the addition of copper and sulfur. The crystalline properties of the resulting films are similar to those leading to high efficiency solar cells. An energy conversion efficiency of 6.7% has been attained with a 1.5 μm thick CuInS2 layer and a standard CdS buffer layer/ZnO window structure. Improved performances can be expected through the growth of thicker absorbers.

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