TY - GEN
T1 - Effect of process parameter variation in deposited emitter and buffer layers on the performance of silicon heterojunction solar cells
AU - Das, Ujjwal
AU - Bowden, Stuart
AU - Burrows, Michael
AU - Hegedus, Steven
AU - Birkmire, Robert
PY - 2006
Y1 - 2006
N2 - Heterostuctures of amorphous silicon (a-Si:H) and n-type crystalline silicon (c-Si) were investigated with special emphasis on the effect of emitter [p (a-Si:H)] and buffer layer [i (a-Si:H)] processing conditions. Boron (B)-doping in emitter layer sensitively affects performance of heterojunction solar cells without a buffer layer and controls valence band offset (ΔEv) at the hetero-interface. Insertion of 10 nm buffer layers passivate c-Si surface very efficiently albeit with an increased ΔE V and poor carrier transport across the heterojunction. Consequently, an open circuit voltage (VOC) of 700 mV was achieved with low fill factor (FF). Buffer layers deposited at high H2/SiH4 ratio (R=40) and/or at higher temperature (300°C) improve FF (77%) but lead to lower VOC (638 mV). Therefore, the emitter and the buffer layer process parameters play important roles to determine the band alignment and carrier transport across the a-Si:H / c-Si hetero-interface.
AB - Heterostuctures of amorphous silicon (a-Si:H) and n-type crystalline silicon (c-Si) were investigated with special emphasis on the effect of emitter [p (a-Si:H)] and buffer layer [i (a-Si:H)] processing conditions. Boron (B)-doping in emitter layer sensitively affects performance of heterojunction solar cells without a buffer layer and controls valence band offset (ΔEv) at the hetero-interface. Insertion of 10 nm buffer layers passivate c-Si surface very efficiently albeit with an increased ΔE V and poor carrier transport across the heterojunction. Consequently, an open circuit voltage (VOC) of 700 mV was achieved with low fill factor (FF). Buffer layers deposited at high H2/SiH4 ratio (R=40) and/or at higher temperature (300°C) improve FF (77%) but lead to lower VOC (638 mV). Therefore, the emitter and the buffer layer process parameters play important roles to determine the band alignment and carrier transport across the a-Si:H / c-Si hetero-interface.
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U2 - 10.1109/WCPEC.2006.279648
DO - 10.1109/WCPEC.2006.279648
M3 - Conference contribution
AN - SCOPUS:41749108173
SN - 1424400163
SN - 9781424400164
T3 - Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion, WCPEC-4
SP - 1283
EP - 1286
BT - Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion, WCPEC-4
PB - IEEE Computer Society
T2 - 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion, WCPEC-4
Y2 - 7 May 2006 through 12 May 2006
ER -