SeS2 assisted bonding of GaAs to Si - A new method for wafer bonding

A new technique namely chemical bonding by surface modification (CBSM) has been developed to bond GaAs thin films on Si substrate. The bonded GaAs epi layer, detached from its orginal substrate in conjunction with epitaxial li ft-off (ELO) process, possessed smooth surface morphology and exhibited uni form bonding across the interface. The X-ray full width at half maximum (FW HM) of 16 are-sec from double crystal X-ray diffraction (DCD) and no peak w avelength shift from photoluminscence (PL) measurements reflected the high crystalline quality of the bonded films. The depth profile by XPS revealed at the interface the occurrence of surface modification. The surface modifi cation resulted in the formation of Ga2Se3 and SiS2, which attributed for t he strong and high quality bonding between GaAs and Si. (C) 2000 Elsevier S cience B.V. All rights reserved.