Multi-phase back contacts for CIS solar cells
Abstract
Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe{sub 2} where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Momore »
- Inventors:
- Issue Date:
- Research Org.:
- National Renewable Energy Laboratory (NREL), Golden, CO (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 170450
- Patent Number(s):
- 5477088
- Application Number:
- 08/060,284
- Assignee:
- Rockett, A.A.; Yang, L.C.
- DOE Contract Number:
- AC02-83CH10093
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 1993 May 12; Other Information: PBD: 19 Dec 1995
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; COPPER SELENIDE SOLAR CELLS; DESIGN; FABRICATION; ELECTRIC CONTACTS; INDIUM SELENIDE SOLAR CELLS; GALLIUM SELENIDES; GRAIN SIZE; VAPOR DEPOSITED COATINGS; MOLYBDENUM; PHOTOVOLTAIC CONVERSION; ENERGY EFFICIENCY
Citation Formats
Rockett, Angus A., and Yang, Li-Chung. Multi-phase back contacts for CIS solar cells. United States: N. p., 1995.
Web.
Rockett, Angus A., & Yang, Li-Chung. Multi-phase back contacts for CIS solar cells. United States.
Rockett, Angus A., and Yang, Li-Chung. Tue .
"Multi-phase back contacts for CIS solar cells". United States.
@article{osti_170450,
title = {Multi-phase back contacts for CIS solar cells},
author = {Rockett, Angus A. and Yang, Li-Chung},
abstractNote = {Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe{sub 2} where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Mo back layer. Solar cells employing In-rich CIS semiconductors bonded to the multi-phase columnar microstructure back layer of this invention exhibit vastly improved photo-electrical conversion on the order of 17% greater than Mo alone, improved uniformity of output across the face of the cell, and greater Fill Factor. 15 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Dec 19 00:00:00 EST 1995},
month = {Tue Dec 19 00:00:00 EST 1995}
}