TY - JOUR
T1 - Defect states determining dynamic trapping-detrapping in β-Ga2O3 field-effect transistors
AU - Polyakov, Alexander Y.
AU - Smirnov, Nikolai B.
AU - Shchemerov, Ivan V.
AU - Chernykh, Sergey V.
AU - Oh, Sooyeoun
AU - Pearton, Stephen J.
AU - Ren, Fan
AU - Kochkova, Anastasia
AU - Kim, Jihyun
N1 - Funding Information:
The work at NUST MISiS was supported in part by the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST (MISiS, K2-2014-055). The research at Korea University was supported by the Technology Development Program to Solve Climate Changes of the National Research Foundation (NRF) funded by the Ministry of Science and ICT (NRF-2017M1A2A2087351). The work at UF is supported by Department of Defense, Defense Threat Reduction Agency, HDTRA1-17-1-011, monitored by Jacob Calkins.
PY - 2019
Y1 - 2019
N2 - β-Ga2O3 is an intriguing material as a channel layer for the next generation high power transistors. To assess the device level effects of the traps in β-Ga2O3, the dynamic dispersion characteristics of a back-gated nanobelt β-Ga2O3 field-effect transistor prepared by mechanical exfoliation from a bulk β-Ga2O3 single crystal was investigated by the dependence of threshold voltage hysteresis on transistor transfer characteristics on the gate voltage ramp, pulsed current-voltage characteristics, and current deep level transient spectroscopy measurements. Current lag in the off-state was related to the presence of electron traps at Ec-0.75 eV, which are also present in bulk crystals and ascribed to Fe impurities or native defects. In the on-state, drain current lag was caused by surface traps with levels at Ec-(0.95–1.1) eV. Optimized passivation layers for β-Ga2O3 are required to prevent the current collapse because the device performances are affected by the environmental molecules adsorbed on the surface. Our work can pave a way to mitigating the defect-related current collapse in β-Ga2O3 electronic devices.
AB - β-Ga2O3 is an intriguing material as a channel layer for the next generation high power transistors. To assess the device level effects of the traps in β-Ga2O3, the dynamic dispersion characteristics of a back-gated nanobelt β-Ga2O3 field-effect transistor prepared by mechanical exfoliation from a bulk β-Ga2O3 single crystal was investigated by the dependence of threshold voltage hysteresis on transistor transfer characteristics on the gate voltage ramp, pulsed current-voltage characteristics, and current deep level transient spectroscopy measurements. Current lag in the off-state was related to the presence of electron traps at Ec-0.75 eV, which are also present in bulk crystals and ascribed to Fe impurities or native defects. In the on-state, drain current lag was caused by surface traps with levels at Ec-(0.95–1.1) eV. Optimized passivation layers for β-Ga2O3 are required to prevent the current collapse because the device performances are affected by the environmental molecules adsorbed on the surface. Our work can pave a way to mitigating the defect-related current collapse in β-Ga2O3 electronic devices.
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U2 - 10.1149/2.0031907jss
DO - 10.1149/2.0031907jss
M3 - Article
AN - SCOPUS:85063266905
VL - 8
SP - Q3013-Q3018
JO - ECS Journal of Solid State Science and Technology
JF - ECS Journal of Solid State Science and Technology
SN - 2162-8769
IS - 7
ER -