Fabrication of thick films of silicon-on-insulator substrates by using a scanning halogen lamp system

A technique for preparing thick films of silicon-on-insulating substrates is presented. We start with a classical deposition of a thin film of polysilicon on patterned stripes of SiO2 grown on Si wafers. The energy of the focused light of a halogen lamp induces a deep melting in the upper part of the substrate. This results in a controlled sinking of the SiO2 strips in the molten silicon. By scanning the molten zone, the silicon solidifies at the leading edge, and the resulting film is made of 20¿40 ¿m-thick stripes of defect-free Si-on-SiO2 separated by seeding areas.