Room-temperature wafer bonding of LiNbO_3 and SiO_2 using a modified surface activated bonding method

摘要

In this paper, we report room-temperature bonding of LiNbO3 (LN) and SiO2/Si for the realization of a LN on insulator (LNOI)/Si hybrid wafer. We investigate the applicability of a modified surface activated bonding (SAB) method for the direct bonding of LN and a thermally grown SiO2 layer. The modified SAB method using ion beam bombardment demonstrates the room-temperature wafer bonding of LN and SiO2. The bonded wafer was successfully cut into 0.5 x 0.5 mm(2) dies without interfacial debonding owing to the applied stress during dicing. In addition, the surface energy of the bonded wafer was estimated to be approximately 1.8 J/m(2) using the crack opening method. These results indicate that a strong bond strength can be achieved, which may be sufficient for device applications. (C) 2018 The Japan Society of Applied Physics.