The gaussian distribution of inhomogeneous barrier heights in PtSi/p-Si Schottky diodes

The current-voltage characteristics of PtSi/p-Si Schottky barrier diodes were investigated in the temperature range of 85-136K and their barrier height (phi(b)), ideality factor (n) and series resistance (R-s) were found to be strongly temperature-dependent. While n decreases, phi(b) increases with increasing temperature and the conventional activation energy plot deviates from linearity. These discrepancies from ideal thermionic emission theory is attributed to Schottky barrier inhomogeneities and the Schottky barrier inhomogeneities are shown to obey a single Gaussian distribution with a mean value of 0.4548 eV and a standard deviation of 0.0607 eV. The modified activation plot which takes into account the barrier height variations through the Gaussian distribution is acceptably linear and gives ((phi) over bar (b)) and A* as 0.4546 eV and 31.47 Acm(-2)K(-2) respectively.