Frequency and temperature-dependent electrical characteristics of Ni/n-GaP/Al Schottky barrier diodes

Abstract

Ni/n-GaP/Al Schottky diodes have been fabricated and their dielectric characteristics have been measured in under vacuum ambient. Parameters such as dielectric constant e & PRIME;, dielectric loss e & DPRIME;, real Z & PRIME; and imaginary Z & DPRIME; impedance, real M & PRIME; and imaginary M & PRIME;& PRIME; electrical modulus, and conductivity & sigma; as a function of frequency f have been measured in the temperature range of 100-320 K with steps of 20 K. The Nyquist plots of (Z & PRIME;-Z & DPRIME;) have shown that non-Debye relaxation phenomena take place in the sample. The conductivity & sigma; measurements at each temperature have shown that both ac and dc conductivities are present in the operating frequency range. The activation energy (Ea) has been calculated using an Arrhenius equation from the peak frequency of both Z & DPRIME;-f and M & DPRIME;-f plots at each temperature. The obtained activation energies values have been obtained as 18 meV and 4.37 meV from the Z & DPRIME;-f plot and 16.33 meV and 4.37 meV from the M & DPRIME;-f plot for the high and low-temperature regions, respectively. The activation energies are originated from shallow interface states located near and relatively far from the bottom of the conduction band.