A comparative analysis of thermal gate oxide on strained Si/relaxed SiGe layer for reliability prediction of strained Si MOSFETs

Although the high mobility channel was formed with the strained Si layer on the fully relaxed Si0.8Ge0.2 buffer layer, the mobility was severely attenuated with increasing the gate bias due to the degraded interface. The quality of oxide grown on strained Si was found to be worse than that for the unstrained Si in terms of fixed oxide charge, interface state density, oxide traps. Also the degraded oxide quality induces high leakage current, it can be a severe source which gives rise to potential reliability issues and performance degradation in strained Si devices.