Smart-Cut® Technology: an Industrial Application of Ion Implantation Induced Cavities

The Smart-Cut® process is based on proton implantation and wafer bonding. Proton implantation enables delamination of a thin layer from a thick substrate to be achieved whereas the wafer bonding technique enables different multilayer structures to be achieved by transferring the delaminated layer onto a second substrate. One of the best known applications of Smart Cut® is the Silicon On Insulator structure. The physical mechanisms involved in the delamination process are discussed based on the study of Proton-induced microcavity formation during implantation and growth during annealing. The experimental results on the time and temperature required to achieve delamination lead to different activation energies depending on the implantation conditions and resistivity of the substrate. All the experiments indicate that growth of microcavities is mainly controlled by hydrogen diffusion. The growth of these microcavities and the pressure inside them induce delamination when the catastrophic radius of the microcavities is reached.