Frequency effect on electrical and dielectric performance of Au/n-GaAs structure with RF sputtering MoO3 interfacial layer

Abstract

The effect of frequency on the electrical and dielectric properties of the metal-semiconductor structure with Molybdenum trioxide (MoO3) interfacial layer was investigated. MoO3 thin film was deposited n-type (100)-oriented GaAs substrate using RF magnetron sputtering method at substrate temperatures of 200 degrees C. Au was chosen as the metal, and electrical analysis of the Au/n-GaAs structure with MoO3 interfacial layer was performed using capacitance-voltage-frequency (C-V-f) conductance-voltage-frequency (G /omega-V-f) measurements. C-V-f and G/omega-V-f outputs were examined, and it was seen that they have inversion, depletion and accumulation regions. According to the experimental results, it was determined that the C and G/omega values were strongly dependent on frequency and voltage, especially in the accumulation and depletion regions. Here, both C and G/omega values decrease with increasing frequency. The structural resistance was obtained by using the C and G/omega data with the Nicollian-Brews method and the series resistance (R-s) values were determined from there. At 3 V, the R-s values were calculated 454 Omega and 102 Omega for 30 kHz and 1 MHz, respectively. In addition, the C and G/omega values were corrected for the 1 MHz value and a comparative evaluation of the corrected and noncorrected values was made. Moreover, the dielectric parameters of the structure were calculated using the measured C and G/omega data. It was indicated that while dielectric constant and dielectric loss decreased with increasing frequency as in C and G/omega, ac conductivity increased due to a decrease in polarization as frequency increased.