Bonding technology of semiconductor film on piezoelectric substrate using epitaxial lift-off technology

In this paper, we report the results of a study on the basic problems of th e mass production of epitaxial liftoff (ELO) film bonding technology. We pr opose a new releasing method for a large number of semiconductor films usin g polyimide to protect the semiconductor films. We investigated the basic p rocess conditions and successfully released a large number of stripe shaped GaAs films. We also studied the heating method for enhancing the bonding s trength between a small-sized semiconductor film and a piezoelectric substr ate. We investigated the effect of migration of water molecules from the bo nding interfaces using microwave and laser irradiation. We estimated the cr ystallinity of semiconductor films by X-ray diffraction. The results clarif ied that these processes were effective in improving mass productivity on t he fabrication technology of surface acoustic wave (SAW)-semiconductor coup led devices.