Title :
Effect of CdS thickness on CdS/CdTe quantum efficiency [solar cells]
Author :
Granata, J.E. ; Sites, J.R. ; Contreras-Puente, G. ; Compaan, A.D.
Author_Institution :
Dept. of Phys., Colorado State Univ., Fort Collins, CO, USA
Abstract :
A significant photocurrent loss in CdS/CdTe solar cells is due to window-layer CdS bandgap absorption below 520 nm. This work evaluates a coordinated effort by six laboratories to optimize the CdS thickness to increase CdTe cell performance, Quantum efficiency is used to compare CdS/CdTe solar cell photocurrent performance for various CdS window-layer thicknesses in the range of 400 Å to 2500 Å. The contribution to Jsc from wavelengths below 520 nm, corresponding to the CdS bandgap, shows a photocurrent difference of roughly 5 mA/cm2 between the practical thick and thin CdS layer thicknesses, corresponding to a possible efficiency difference between 12% and 15%. Additionally, there appears to be a process-dependent lower limit to the minimum CdS thickness for good-junction cells
Keywords :
II-VI semiconductors; cadmium compounds; energy gap; p-n heterojunctions; semiconductor device testing; short-circuit currents; solar cells; 12 to 15 percent; 400 to 2500 angstrom; CdS-CdTe; CdS-CdTe solar cells; bandgap absorption; photocurrent loss; photocurrent performance improvement; quantum efficiency; semiconductor; window-layer thickness; Absorption; Cascading style sheets; Chemical vapor deposition; Glass; Laboratories; Photoconductivity; Photonic band gap; Photovoltaic cells; Physics; Voltage;
Conference_Titel :
Photovoltaic Specialists Conference, 1996., Conference Record of the Twenty Fifth IEEE
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-3166-4
DOI :
10.1109/PVSC.1996.564262
