The effect of frequency and temperature on capacitance/conductance–voltage (C/G–V) characteristics of Au/n-GaAs Schottky barrier diodes (SBDs)

The capacitance–voltage (C–V) and conductance–voltage (G/ω–V) characteristics of the Au/n-GaAs Schottky barrier diodes (SBDs) have been investigated for 10, 100 and 500 kHz at 80 and 280 K. To evaluate the reason of non-ideal behavior in C–V and G/ω–V plots, the measured C and G/ω values were corrected by taking into accounts series resistance effect. Experimental results show that the values of C and G/ω were found to be a strong function of interface states (Nss) at inverse and depletion regions especially at low frequencies, but Rs is effective only at the accumulation region especially at high frequencies. Such behavior of the C and G/ω values may be attributed to an increase in polarization especially at low frequencies and the existence of Nss or dislocations between metal and semiconductor. It can be concluded that the increase in C and G/ω at low frequencies especially at weak and depletion regions results from the existence of Nss. The values of doping concentration (Nd) and barrier height (BH) between metal and semiconductor were also obtained from the linear part of high frequency (500 kHz) C−2 vs. V plots at 80 and 280 K, respectively.