“…8 While the Si buffer layer affords a gate oxide (SiO 2 ) with outstanding electrical properties as well as a stable, high-quality Si/SiO 2 interface, it can also result in a parasitic, decreased mobility conduction channel, limiting the ultimate mobility that could be achieved with strained Si x Ge 1-x (100). 8,9 In addition, because of direct tunneling and concerns regarding dielectric reliability and breakdown strength as well as resistance to dopant penetration, ultrathin SiO 2 must be replaced by a physically thicker gate oxide material with a higher dielectric constant. 10 Therefore, in order to fully exploit the high carrier mobility in the case of high-performance SiGe-based devices, it is desirable to deposit a stable high-κ dielectric material in direct contact with Si x Ge 1-x (100).…”