Pick toThis paper strain silicon MOS interface characteristics of system, in-depth research.Aiming at the common MOS strain silicon surface in gully device structure and established a bar pressure and trans layer between the minority carriers concentration of models. Based on this model, the paper studies the strain of capacitor voltage characteristic silicon MOS. The results show that the strain Si/relaxation SiGe heterojunction photonic bandgap sent on the electron and the formation of cavity restrictions, at ambient temperature, strain silicon MOS C V curve can run area one or trans area side of "bench" phenomenon, this "bench" phenomenon with strain Si/relaxation SiGe denotation layer of doping concentration changes.Using the high frequency C strain silicon V experimental results, thoroughly discussed the strain Si/SiO2 system interface charge, points out its characteristics of interface is given, and the influence of the improvements. Finally, based on body silicon MOS high-frequency capacitance measurement method improvement and corrections, measured and calculated the strain Si/SiO2 interface interface state density.In the device physics, was presented based on the strain simi-emperical silicon n - MOSFET trans channel electronic mobility model. The model considers the lattice, from change impurities, surface phonons, interface charge and interfacial rough, etc in gully mobility mechanism on the scattering of influence, and considers the trans electronic shielding effect, finally use of Matlab software are simulated, and the simulation results with experiments with a very good match.Keywords: strain silicon MOS C V characteristics interface state reliability