Title :
Preparation of undoped and doped microcrystalline silicon (μc-Si:H) by VHF-GD for p-i-n solar cells
Author :
Flückiger, R. ; Meier, J. ; Keppner, H. ; Götz, M. ; Shah, A.
Author_Institution :
Inst. de Microtech., Neuchatel Univ., Switzerland
Abstract :
The electronic transport properties of μc-Si:H materials were investigated. The μc-Si:H was deposited by the very high frequency-glow discharge (VHF-GD) technique at an RF-excitation of 70 MHz. Very thin ⟨p⟩ doped layers (100-400 Å) were studied. Conductivities higher than 10-3 (Ω cm)-1 could be achieved for films thicker than 150 Å. The as-deposited μc-Si:H is a slightly ⟨n⟩-type material and compensation was obtained by μ-doping with boron. Light-induced degradation of the compensated film showed better stability than for a-Si:H. Entirely μc-Si:H p-i-n solar cells were prepared by incorporating the compensated layer in the structure. The μc-Si:H cells show indeed an increase in the spectral response beyond 750 nm compared to amorphous silicon solar cells. These results indicate that the slightly doped μc-Si:H is a new promising photovoltaically active material, which merits closer investigation
Keywords :
amorphous semiconductors; elemental semiconductors; hydrogen; p-n heterojunctions; plasma deposited coatings; plasma deposition; semiconductor doping; semiconductor thin films; silicon; solar cells; 100 to 400 angstrom; 70 MHz; RF excitation; Si:H; VHF glow discharge; active material; compensation; doping; electronic transport properties; microcrystalline; p-i-n solar cells; spectral response; stability; Boron; Conducting materials; Conductive films; Conductivity; Degradation; Frequency; PIN photodiodes; Photovoltaic cells; Silicon; Stability;
Conference_Titel :
Photovoltaic Specialists Conference, 1993., Conference Record of the Twenty Third IEEE
Conference_Location :
Louisville, KY
Print_ISBN :
0-7803-1220-1
DOI :
10.1109/PVSC.1993.347112
