In this brief, the effect of biaxial tensile strain on the hole mobility limited by substrate-impurity and interface-state Coulomb scatterings ($mu_{rm sub}$ and $mu_{rm it}$, respectively) in an inversion layer of $(hbox{100})/langle hbox{110} rangle$ pMOSFETs is investigated experimentally with strained-Si (s-Si) channels on relaxed $ hbox{Si}_{1 - x}hbox{Ge}_{x}break (x = hbox{0.1}$#x2013;$ hbox{0.4})$ substrates. Our results show that biaxial tensile strain degrades the hole mobility limited by substrate-impurity Coulomb scattering $(mu_{rm sub})$ , while it enhances the hole mobility limited by interface-state Coulomb scattering $(mu_{rm it})$ because of the increase in the average distance between holes and scattering centers at the $hbox{Si}/hbox{SiO}_{2}$ interface after the tensile strain. These trends are opposite to that of electron ones. The different strain dependence between electrons and holes in terms of $mu_{rm sub}$ and $mu_{rm it}$ can be explained by a universal two-band model based on the subband structures of electrons and holes.
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