Formation of silicon on plasma synthesized SiOxNy and reaction mechanism

The application of silicon-on-insulator (SOI) substrates to high-power integrated circuits is hampered by self-heating effects due to the poor thermal conductivity of the buried SiO2 layer. We propose to replace the buried SiO2 layer in SOI with a plasma synthesized SiOxNy, thin film to mitigate the self-heating effects. The SiOxNy films synthesized on silicon by plasma immersion ion implantation (PHI) exhibit outstanding surface topography, and excellent insulating characteristics are maintained up to an annealing temperature of 1100 degrees C. Hence, the polycrystallization in our SiOxNy materials is insignificant during conventional complementary metal oxide silicon (CMOS) processing. Using Si/SiOxNy direct bonding and the hydrogen-induced layer transfer, a silicon-on-SiOxNy structure has been successfully fabricated. Cross-sectional high-resolution transmission electron microscopy (HRTEM) and spreading resistance profiling (SRP) reveal that the bonded interface is abrupt and the top Si layer exhibits nearly perfect single crystalline quality. The reaction mechanism of SiOxNy and Si wafer bonding are also discussed. (c) 2004 Elsevier B.V. All rights reserved.