Performance Improvement of La_2O_3/ p-GaAs MOS Capacitor by using Si Pasivation Layer

摘要

The RF sputtered La_2O_3/ p-GaAs MOS capacitors with and without Si interface passivation layer (IPL) have been fabricated and characterized. It has been observed that the presence of (La_2O_3)_(1-x)(SiO_2)_x at the interface improved the device characteristics in terms of oxide capacitance (~3.3 fF/μm~2), frequency dispersion (~8%) and interface state density (~1.2×10~(12) cm~(-2) eV~(-1) ). The best device performance was obtained for Al/ La_2O_3/Si/p-GaAs samples annealed at 500°C.