Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

CdSxTe1-x Alloying in CdS/CdTe Solar Cells

Conference ·
; ; ; ; ; ;
A CdS{sub x}Te{sub 1-x} layer forms by interdiffusion of CdS and CdTe during the fabrication of thin film CdTe photovoltaic (PV) devices. The CdS{sub x}Te{sub 1-x} layer is thought to be important because it relieves strain at the CdS/CdTe interface that would otherwise exist due to the 10% lattice mismatch between these two materials. Our previous work has indicated that the electrical junction is located in this interdiffused CdS{sub x}Te{sub 1-x} region. Further understanding, however, is essential to predict the role of this CdS{sub x}Te{sub 1-x} layer in the operation of CdS/CdTe devices. In this study, CdS{sub x}Te{sub 1-x} alloy films were deposited by radio-frequency magnetron sputtering and coevaporation from CdTe and CdS sources. Both radio-frequency-magnetron-sputtered and coevaporated CdS{sub x}Te{sub 1-x} films of lower S content (x < 0.3) have a cubic zincblende (ZB) structure akin to CdTe, whereas those of higher S content have a hexagonal wurtzite (WZ) structure like that of CdS. Films become less preferentially oriented as a result of a CdCl{sub 2} heat treatment at {approx}400 C for 5 min. Films sputtered in a 1% O{sub 2}/Ar ambient are amorphous as deposited, but show CdTe ZB, CdS WZ, and CdTe oxide phases after a CdCl{sub 2} heat treatment. Films sputtered in O{sub 2} partial pressure have a much wider bandgap than expected. This may be explained by nanocrystalline size effects seen previously for sputtered oxygenated CdS (CdS:O) films.
Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1043774
Report Number(s):
NREL/CP-5200-51737
Country of Publication:
United States
Language:
English

References (4)

Nanostructured CdS:O film: preparation, properties, and application journal March 2004
Phase behavior in the CdTe–CdS pseudobinary system
  • McCandless, Brian E.; Hanket, Gregory M.; Jensen, D. Garth
  • Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 20, Issue 4 https://doi.org/10.1116/1.1487872
journal July 2002
Phase Diagram of the CdS-CdTe Pseudobinary System journal August 1973
Optical Energy Gap of the Mixed Crystal CdS x Te 1- x journal October 1973

Similar Records

CdS/CdTe Solar Cells Containing Directly-Deposited CdSxTe1-x Alloy Layers
Conference · Fri Dec 31 23:00:00 EST 2010 · OSTI ID:1049624
CdS/CdTe Solar Cells Containing Directly Deposited CdSxTe1-x Alloy Layers: Preprint
Conference · Fri Jul 01 00:00:00 EDT 2011 · OSTI ID:1026572
CdSxTe1-x Alloying in CdS/CdTe Solar Cells
Conference · Sun May 01 00:00:00 EDT 2011 · OSTI ID:1018080

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
ALLOYS
CdTe photovoltaic
FABRICATION
HEAT TREATMENTS
MAGNETRONS
OXIDES
PARTIAL PRESSURE
PV
SOLAR CELLS
SPUTTERING
STRAINS
THIN FILMS
solar
thin film