GaAs film on Si substrate transplanted from GaAs/Ge structure by direct bonding

Abstract

A process to transplant GaAs film from a Ge substrate to Si substrate using a direct bonding method is proposed. The scanning electron microscopy picture shows that the GaAs film is uniformly transplanted from Ge to Si. The high-resolution transmission electron microscopy image shows that GaAs is connected to Si by the covalent bonds. The stress of the bonded GaAs on Si is compared with GaAs/GaAs and heteroepitaxially grown GaAs/Ge(before bonding) by a 4.2 K photoluminescence method. The difference in the residual stress between the bonded GaAs/Si sample and GaAs/Si grown by two-step growth is explained by a thermal stress relaxation mechanism during the cooling process.