On the profile of frequency dependent interface states and series resistance in Au/p-InP SBDs prepared with photolithography technique

The frequency dependent of the forward and reverse bias capacitance-voltage(C-V) and conductance-voltage(G/w-V) characteristics of Au/p-InP SBDs have been investigated in the frequency range of 20 kHz-10 MHz and voltage range of 5-5 V at room temperature.The effects of surface states(Nss) and series resistance(Rs) on C-V and G/w-V characteristics have been investigated in detail.The frequency dependent N ss and R s profiles were obtained for various applied bias voltages.The experimental results show that the main electrical parameters of Au/p-InP SBD such as barrier height(ΦB),the density of acceptor concentration(NA),N ss and R s were found strongly frequency and voltage dependent.The values of C and G/w decrease with increasing frequency due to a continuous distribution of N ss localized at the metal/semiconductor(M/S) interface.The effect of R s on C and G is found considerably high especially at high frequencies.Therefore,the high frequencies of the values of C and G were corrected for the effect of R s in the whole measured bias range to obtain the real diode capacitance C c and conductance G c using the Nicollian and Goetzberger technique.The distribution profile of R s-V gives a peak depending on the frequency especially at low frequencies and disappears with increasing frequencies due to the existence of N ss at the M/S interface.