An electron spin resonance analysis has been carried out of the intrinsic point defects in (100)Si∕SiO2 entities thermally grown at 800°C on biaxial tensile strained Si (s-Si). As compared to coprocessed standard (100)Si∕SiO2, a significant reduction (>50%) is observed in the inherent density of the trivalent Pb-type interface defects (Pb0,Pb1). With the Pb0’s established as detrimental fast interface traps, this result may adduce one more reason for the observed enhancement of device channel carrier mobility with increasing Si substrate tensile strain as well as reduction in 1∕f noise. The s-Si∕SiO2 interface exhibits a generally superior device grade quality.