Demonstration of unpinned GaAs surface and surface inversion with gate dielectric made of Si_3N_4

摘要

The authors have measured the electrical properties of metal insulator semiconductor capacitors of GaAs, with ex situ jet-vapor-deposited Si_3N_4 as a gate dielectric. Unpinning of GaAs surface was demonstrated by ac conductance and capacitance-voltage (C-V) measurement; GaAs surface inversion has been demonstrated by quasistatic C-V and hysteresis C-V measurements. Hydrogen plasma predeposition treatment at 200℃ has been shown to reduce interface-state density. The lowest interface-state density that the authors measured was 9 x 10~(11)/cm~2/eV at 0.57 eV above E_V for p-type GaAs, and the smallest hysteresis window was 100 mV.