Title :
Light-induced degradation of thin film amorphous and microcrystalline silicon solar cells
Author :
Meillaud, F. ; Vallat-Sauvain, E. ; Niquille, X. ; Dubey, M. ; Bailat, J. ; Shah, A. ; Ballif, C.
Author_Institution :
Inst. of Microtechnology, Neuchatel Univ., Switzerland
Abstract :
Absorption spectra of two dilution series of microcrystalline solar cells deposited by VHF-PECVD were measured by FTPS. The dilution series were composed of pin and of nip cells, with i-layers ranging from highly crystalline to mainly amorphous. This paper evaluates stability of the cells when exposed to white light (AM 1.5-like spectrum). Defect-related absorption is minimum for cells of medium crystallinity (deposited in the transition region); but is increased for theses cells by a factor 2 to 4 under light-soaking. It still remains lower than that of highly crystalline cells which show very little degradation. Variation of electrical parameters is also investigated as a function of light soaking and annealing steps. Cells of medium crystallinity show approximately 10% reversible relative efficiency loss after 1000 hours of light soaking.
Keywords :
Fourier transform spectra; amorphous semiconductors; annealing; crystal microstructure; defect absorption spectra; elemental semiconductors; photoconductivity; plasma CVD; silicon; solar cells; thin film devices; 1000 hour; FTPS; Si; VHF-PECVD; absorption spectra; annealing; defect-related absorption; dilution; i-layers; light-induced degradation; light-soaking; microcrystalline silicon solar cells; nip cells; pin cells; thin film amorphous silicon solar cells; Absorption; Amorphous materials; Crystalline materials; Crystallization; Degradation; Photovoltaic cells; Semiconductor thin films; Silicon; Spectroscopy; Stability;
Conference_Titel :
Photovoltaic Specialists Conference, 2005. Conference Record of the Thirty-first IEEE
Print_ISBN :
0-7803-8707-4
DOI :
10.1109/PVSC.2005.1488405
