Temperature dependent currentvoltage (IV) characteristics of Au/n-Si (1 1 1) Schottky barrier diodes with PVA(Ni,Zn-doped) interfacial layer

WOS: 000292408500010Current-voltage (I-V) characteristics of Au/PVA/n-Si (1 1 1) Schottky barrier diodes (SBDs) have been investigated in the temperature range 80-400 K. Here, polyvinyl alcohol (PVA) has been used as interfacial layer between metal and semiconductor layers. The zero-bias barrier height (Phi(B0)) and ideality factor (n) determined from the forward bias I-V characteristics were found strongly dependent on temperature. The forward bias semi-logarithmic I-V curves for different temperatures have an almost common cross-point at a certain bias voltage. The values of Phi(B0) increase with the increasing temperature whereas those of n decrease. Therefore, we have attempted to draw Phi(B0) vs. q/2kT plot in order to obtain evidence of a Gaussian distribution (GD) of the barrier heights (BHs). The mean value of BH (Phi) over bar (B0) and standard deviation (sigma(0)) were found to be 0.974 eV and 0.101 V from this plot, respectively. Thus, the slope and intercept of modified In(I-0/T-2)-q(2)sigma(2)(0)/2(kT)(2) vs. q/kT plot give the values of (Phi) over bar (B0) and Richardson constant (A*) as 0.966 eV and 118.75 A/cm(2)K(2), respectively, without using the temperature coefficient of the BH. This value of A* 118.75 A/cm(2)K(2) is very close to the theoretical value of 120 A/cm(2)K(2) for n-type Si. Hence, it has been concluded that the temperature dependence of the forward I-V characteristics of Au/PVA/n-Si (1 1 1) SBDs can be successfully explained on the basis of the Thermionic Emission (TE) theory with a GD of the BHs at Au/n-Si interface.Gazi University [04/2010-27]This work is supported by Gazi University Scientific Research Project numbered 04/2010-27