Reverse saturation current , theoretically , increases by 8% per oC for silicon and 11% per oC for germanium. But from experimental data it is found that that reverse saturation current increases by 7% per oC for both silicon and germanium. This is because a surface leakage current component of reverse saturation current is independent of temperature. Since (1.07)10 =2.0 (approx.), the reverse saturation current approximately doubles for every 10oC rise in temperature.