Epi-less bond-and-etch-back silicon-on-insulator by MeV ion implantation

A modified approach to silicon-on-insulator (SOI) by bond-and-etch-back technology was studied where a high-energy (MeV) boron implant was utilized as an etch stop to eliminate the need for an epitaxial layer growth in forming a device film. Also a second (retro) MeV implant, applied after the first stage of the etch-back process, was investigated as an improved method for achieving uniform thinning of a thick (3 μm) SOI film. Significantly improved thickness uniformities (σ<10 nm across a 3×3 in. area) were obtained by this method for a 490-nm-thick silicon device film.