Study on density of state of strained Si1−xGex

The strained Si technology is a research emphasis in the modern microelectronic field. Density of state (DOS) is an important physical parameter in strained Si materials. Based on KP perturbation theory related to stress, the models of DOS effective mass of electron and hole near the bottom of conduction band and the top of valence band were obtained in strained Si1−xGex. Furthermore, quantitative analytical models of DOS of electron and hole near the bottom of conduction band and the top of valence band was established in the trained Si1−xGex grown from (001), (101) and (111) substrates respectively. The models were simulated and analyzed using Matlab software. It was found that their DOS versus energy were parabola curves and have significant influence under the stress. The quantized models obtained can provide valuable references to the understanding on strained Si1−xGex materials and the research on physical properties of devices.