Electrical Transport Study on Pd/n-SiGe/Si Schottky Diodes

It is shown in the present study that the strong temperature dependence of Pd/n-SiGe/Si Schottky diode parameters, obtained experimentally, could not be fully explained by considering the combined effects of tunneling, recombination, image-force lowering and series resistance. A satisfactory explanation, however, could be achieved within the framework of a modified thermionic emission theory with the assumption that the barrier potential at the Pd/SiGe interface is not flat but fluctuates around a mean value of 0.8 eV with a standard deviation of 84 meV. This mean barrier height is very close to the one derived from C-V data.