Trapping effects in Al2O3/AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistor investigated by temperature dependent conductance measurements

摘要

Frequency dependent conductance measurements at varied temperature between 25 and 260 °Cnwere performed to analyze trapping effects in the Al2O3 /AlGaN/GaN metal-oxide-semiconductornheterostructure field-effect transistors. The trap states with a time constant u0001T,fu0003u00010.1–1u0002 u0002s u0001fastu0002nand u0001T,s =10 ms u0001slowu0002 were identified. The conductance measurements at increased temperaturesnmade it possible to evaluate the fast trap states in about a four times broader energy range than thatnfrom room temperature measurement. The density of the fast traps decreased from 1.4nu00031012ncm−2neV−1nat an energy of 0.27 eV to about 3u00031011ncm−2neV−1nat ET=0.6 eV. The densitynof the slow traps was significantly higher than that of the fast traps, and it increased with increasedntemperature from about 3u00031012ncm−2neV−1nat 25–35 °C to 8u00031013ncm−2neV−1nat 260 °C.n© 2010 American Institute of Physics. u0004doi:10.1063/1.3275754