TY - GEN
T1 - Substitution of silver electrode with an abundant metal - A fundamental study
AU - Tao, M.
PY - 2011
Y1 - 2011
N2 - One of the fundamental bottlenecks for crystalline-Si solar cells to reach a terawatt scale is the scarcity of silver, which is used as the front finger electrode in most commercial Si solar cells today. In this paper, we examine some of the challenges related to low work-function abundant metals, such as aluminum and titanium, as a potential substitution for silver. These challenges include material resistivity, resistance to oxidation, contact resistance and alloying with Si. Valence-mending passivation is proposed as a potential solution to some of the most fundamental challenges including low Schottky barrier to n-type Si for low contact resistance and suppression of aluminum alloying with Si to prevent unintentional p-type doping into n-type Si. Preliminary results are presented on Al and Ti contacts to valence-mended Si(100) surface. Valence-mending passivation allows record-low Schottky barriers of less than 0.1 eV on n-type Si with aluminum and titanium, leading to a 29x reduction in specific contact resistance between titanium and lightly-doped n-type Si. It also suppresses silicidation on Si(100) surface up to ∼400°C with titanium as well as nickel.
AB - One of the fundamental bottlenecks for crystalline-Si solar cells to reach a terawatt scale is the scarcity of silver, which is used as the front finger electrode in most commercial Si solar cells today. In this paper, we examine some of the challenges related to low work-function abundant metals, such as aluminum and titanium, as a potential substitution for silver. These challenges include material resistivity, resistance to oxidation, contact resistance and alloying with Si. Valence-mending passivation is proposed as a potential solution to some of the most fundamental challenges including low Schottky barrier to n-type Si for low contact resistance and suppression of aluminum alloying with Si to prevent unintentional p-type doping into n-type Si. Preliminary results are presented on Al and Ti contacts to valence-mended Si(100) surface. Valence-mending passivation allows record-low Schottky barriers of less than 0.1 eV on n-type Si with aluminum and titanium, leading to a 29x reduction in specific contact resistance between titanium and lightly-doped n-type Si. It also suppresses silicidation on Si(100) surface up to ∼400°C with titanium as well as nickel.
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U2 - 10.1109/PVSC.2011.6186564
DO - 10.1109/PVSC.2011.6186564
M3 - Conference contribution
AN - SCOPUS:84861017396
SN - 9781424499656
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 2947
EP - 2951
BT - Program - 37th IEEE Photovoltaic Specialists Conference, PVSC 2011
T2 - 37th IEEE Photovoltaic Specialists Conference, PVSC 2011
Y2 - 19 June 2011 through 24 June 2011
ER -