On the analysis of the leakage current in Au/Ca3Co4Ga0.001Ox/n-Si structure in the temperature range of 80–340 K

Abstract

The temperature dependent reverse bias leakage current–voltage (Ir–Vr) of the Au/Ca3Co4Ga0.001Ox/n-Si structure has been investigated in the temperature range of 80–340K. The Ln(Jr/Er) vs E0.5 plots show straight lines with different slopes in the intermediate reverse bias voltages for each temperature. Both the intercepts B(T) and slopes m(T) values were obtained from these plots for each temperature. Their values vs q/kT plots were drawn and they show a linear behavior except for two low temperatures (80 and 120K). The dielectric constant (εs) of interfacial Ca3Co4Ga0.001Ox layer and the barrier height (ϕt) which is necessary electron emission from the trap values were found from the slope of these plots, respectively. Experimental results show that the Ir–Vr characteristics can be well described by the electric field dependence so the dominant conduction mechanisms are either Frenkel–Poole emission (FPE) or Schottky emission (SE) in this structure. The εs and ϕt values were found as 3.1 and 37.1meV, respectively. It is clear that the value of ϕt is considerably low and the value of dielectric constant (3.1) is closed to the dielectric value conventional of SiO2 insulator layer. These results confirmed that the (Ca3Co4Ga0.001Ox) interfacial layer can be used instead of a conventional of SiO2 insulator layer in the terms of flexibility, easy production and low cost.