The impact of germanium in strained Si/relaxed Si_1-xGe _x on carrier performance in non-degenerate and degenerate regimes

The impact of the fraction of germanium on the carrier performance of two-dimensional strained silicon, which embraces both the non-degenerate and degenerate regimes, is developed. In this model, the Fermi integral of order zero is employed. The impact of the fraction of germanium on the relaxed Si _1-xGe_x substrate (x), carrier concentration and temperature is reported. It is revealed that the effect of x on the hole concentration is dominant for a normalized Fermi energy of more than three, or in other words the non-degenerate regime. On the contrary, the x gradient has less influence in the degenerate regime. Furthermore, by increasing x there is an increase in the intrinsic velocity, particularly with high carrier concentration and temperature.