Direct bonding of LiNbO3 and SiC wafers at room temperature

Application of the surface activated bonding (SAB) method to direct bonding of LiNbO3 and SiC was investigated. SAB using argon fast atom beam bombardment resulted in the successful formation of a room-temperature bonded LiNbO3/SiC wafer for the first time. Cross-sectional transmission electron microscopy (TEM) observations showed a void-free bonded interface at the atomic level. The bonded interface had an amorphous-like layer that was a few nanometers thick, which was considered to be formed during the bombardment process. The resulting LiNbO3/SiC structure can be utilized to realize a new configuration of various devices including surface acoustic wave filters for use in high-power applications that can satisfy both temperature compensation and heat dissipation requirements. (C) 2019 Published by Elsevier Ltd on behalf of Acta Materialia Inc.