Integration of Si and SiGe with Al2O3 (sapphire)

Through the characterization of structural defects in bonded silicon on sap phire handle-substrates (SOS) that develop with exposure to device processi ng temperatures, we have investigated and implemented a methodology to stud y wafer bonding reaction chemistry. In this context, we present the result and analysis of this development which provides (through LPCVD SiO2 mitigat ion of bond reaction-induced bubbles) the dislocation-free bonded bulk-qual ity thin silicon layers ( < 100 nm thick) on sapphire or bonded strain reli eved silicon germanium Si1-xGex (x greater than or equal to 0.35) layers on sapphire for device fabrication processes. The resulting bonded layers hav e excellent structural properties, as evidenced by (1) X-ray diffraction (p eak position and peak breadth) before and after exposure to elevated temper atures and (2) cross-sectional TEM. (C) 2001 Elsevier Science B.V. All righ ts reserved.