Title :
Non-uniformity mitigation in CdTe solar cells: the effects of high-resistance transparent conducting oxide buffer layers
Author :
Feldman, S.D. ; Mansfield, L. ; Ohno, T.R. ; Kaydanov, V. ; Beach, J.D. ; Nagle, T.
Author_Institution :
Dept. of Phys., Colorado Sch. of Mines, USA
Abstract :
High-resistance transparent conducting oxide buffer layers (HRTs) are commonly added between the doped transparent conducting oxide (TCO) and CdS in both CdTe and Cu(In,Ga)Se2 (CIGS) based solar cells. The addition of the HRT is known to increase efficiency and has been employed in the production of record CdTe and CIGS devices. Here, we directly and unambiguously observe the non-uniformity mitigation effects of the HRT in CdTe cells through spatially resolved electroluminescence and light-beam induced current measurements. This decrease in non-uniformity has been measured in CdTe cells prepared both at the National Renewable Energy Laboratory and at the Colorado School of Mines both with and without HRT layers. Our measurements suggest that the nonuniformity is caused by thin CdS regions.
Keywords :
II-VI semiconductors; OBIC; buffer layers; cadmium compounds; electroluminescence; solar cells; CIGS based solar cells; CdTe; CdTe solar cells; Cu(In,Ga)Se2 based solar cells; doped transparent conducting oxide; high-resistance buffer layers; light-beam induced current measurement; nonuniformity mitigation; spatially resolved electroluminescence; thin CdS regions; transparent conducting oxide buffer layers; Buffer layers; Current measurement; Electroluminescence; Energy measurement; Energy resolution; Laboratories; Photovoltaic cells; Production; Renewable energy resources; Spatial resolution;
Conference_Titel :
Photovoltaic Specialists Conference, 2005. Conference Record of the Thirty-first IEEE
Print_ISBN :
0-7803-8707-4
DOI :
10.1109/PVSC.2005.1488121
