TY - GEN
T1 - Effect of deposited passivation materials and doping on recombination at III-V surfaces
AU - Kumar, Niranjana Mohan
AU - Chikhalkar, Abhinav
AU - King, Richard R.
N1 - Publisher Copyright:
© 2019 IEEE.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2019/6
Y1 - 2019/6
N2 - Passivation of dangling bonds at surfaces and interfaces is an essential feature of high-efficiency solar cells. The high recombination activity of surface states in III-V semiconductors typically requires epitaxial growth of high-bandgap layers to suppress interface recombination. Surface recombination in III-Vs can be reduced by solution deposition of sulfides, however, the resulting passivation can degrade over time, and surface roughness caused by the passivation can degrade cell performance. In this work, the effects of different passivation materials and techniques, such as atomic layer deposition (ALD) and plasma enhanced chemical vapor deposition (PECVD), on GaAs and InP surfaces are analyzed by direct measurement of the minority-carrier lifetime by time-resolved photoluminescence (TRPL). Recombination parameters due to passivation of surface states are characterized for Al2O3, amorphous silicon (a-Si) and sulfide interfaces on n-type, intrinsic, and p-type GaAs and InP substrates. Al2O3 passivation of n-GaAs has shown 1.35 ns improvement in measured lifetime, while a-Si passivation shows a slight improvement in passivation for n-type GaAs and p-type InP.
AB - Passivation of dangling bonds at surfaces and interfaces is an essential feature of high-efficiency solar cells. The high recombination activity of surface states in III-V semiconductors typically requires epitaxial growth of high-bandgap layers to suppress interface recombination. Surface recombination in III-Vs can be reduced by solution deposition of sulfides, however, the resulting passivation can degrade over time, and surface roughness caused by the passivation can degrade cell performance. In this work, the effects of different passivation materials and techniques, such as atomic layer deposition (ALD) and plasma enhanced chemical vapor deposition (PECVD), on GaAs and InP surfaces are analyzed by direct measurement of the minority-carrier lifetime by time-resolved photoluminescence (TRPL). Recombination parameters due to passivation of surface states are characterized for Al2O3, amorphous silicon (a-Si) and sulfide interfaces on n-type, intrinsic, and p-type GaAs and InP substrates. Al2O3 passivation of n-GaAs has shown 1.35 ns improvement in measured lifetime, while a-Si passivation shows a slight improvement in passivation for n-type GaAs and p-type InP.
KW - AlO
KW - III-V
KW - amorphous silicon
KW - interface states
KW - passivation
KW - surface recombination velocity
UR - http://www.scopus.com/inward/record.url?scp=85081550135&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85081550135&partnerID=8YFLogxK
U2 - 10.1109/PVSC40753.2019.8980913
DO - 10.1109/PVSC40753.2019.8980913
M3 - Conference contribution
AN - SCOPUS:85081550135
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 1039
EP - 1043
BT - 2019 IEEE 46th Photovoltaic Specialists Conference, PVSC 2019
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 46th IEEE Photovoltaic Specialists Conference, PVSC 2019
Y2 - 16 June 2019 through 21 June 2019
ER -