Strain engineering of ultra-thin silicon-on-insulator structures using through-buried-oxide ion implantation and crystallization

We report a novel way of introducing strain in Ultra-Thin Body and Buried-Oxide (UTBB) SOI structures by Ge+ implant into the underlying Si substrate and the formation of localized SiGe regions underneath the buried oxide (BOX) by Crystallization. The localized SiGe regions result in local deformation of the ultra-thin Si. Compressive strain of up to −0.55% and −1.2% were detected by Nano-Beam Diffraction (NBD) at the center and the edge, respectively, of a 50 nm wide ultra-thin Si region located between two local SiGe regions. The under-the-BOX SiGe regions may be useful for strain engineering of ultra-thin body transistors formed on UTBB-SOI substrates.

► A new strain engineering technique for Ultra-Thin Body silicon-on-insulator structure is reported. ► Localized SiGe regions were formed under the buried oxide by Germanium ion-implantation and anneal. ► The localized SiGe regions resulted in local defomation of the overlying ultra-thin Si regions. ► Strain on a 50 nm wide ultra-thin Si region located between two local SiGe regions was examined. ► Very high compressive strain values in ultra-thin Si were detected by Nano-Beam Diffraction (NBD).