TY - GEN
T1 - High efficiency thin film solar cells deposited at the amorphous-tomicrocrystalline transition using SiF4/H2/Ar gas mixtures
AU - Dornstetter, Jean Christophe
AU - Bruneau, Bastien
AU - Bulkin, Pavel
AU - Johnson, Erik V.
AU - Roca I Cabarrocas, Pere
N1 - Publisher Copyright:
© 2014 IEEE.
PY - 2014/10/15
Y1 - 2014/10/15
N2 - Microcrystalline silicon deposited from SiF4/H2/Ar gas mixtures is used as active absorbing layer in thin film solar cells. Best solar cells are made from active layers deposited at the amorphous-to-microcrystalline transition where only a few percent of amorphous phase is present. Based on mass spectrometry measurements, we propose a simple model which accounts for the relevant features of the complex plasma chemistry: namely the depletion of H2, the formation of HF molecules and the amorphous to microcrystalline silicon transition. The specificity of SiF4/H2/Ar plasma is the ability to tightly tune the transition irrespective of the control of the deposition rate. A high crystalline fraction allows thicknesses above 3 μm with a high short-circuit current and no deterioration of the open-circuit voltage.
AB - Microcrystalline silicon deposited from SiF4/H2/Ar gas mixtures is used as active absorbing layer in thin film solar cells. Best solar cells are made from active layers deposited at the amorphous-to-microcrystalline transition where only a few percent of amorphous phase is present. Based on mass spectrometry measurements, we propose a simple model which accounts for the relevant features of the complex plasma chemistry: namely the depletion of H2, the formation of HF molecules and the amorphous to microcrystalline silicon transition. The specificity of SiF4/H2/Ar plasma is the ability to tightly tune the transition irrespective of the control of the deposition rate. A high crystalline fraction allows thicknesses above 3 μm with a high short-circuit current and no deterioration of the open-circuit voltage.
KW - amorphous silicon
KW - amorphous-to-microcrystalline transition
KW - microcrystalline silicon
KW - silicon tetrafluoride
KW - solar-grade material
U2 - 10.1109/PVSC.2014.6925522
DO - 10.1109/PVSC.2014.6925522
M3 - Conference contribution
AN - SCOPUS:84912124852
T3 - 2014 IEEE 40th Photovoltaic Specialist Conference, PVSC 2014
SP - 2839
EP - 2841
BT - 2014 IEEE 40th Photovoltaic Specialist Conference, PVSC 2014
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 40th IEEE Photovoltaic Specialist Conference, PVSC 2014
Y2 - 8 June 2014 through 13 June 2014
ER -