Feasibility study of all-SiC pressure sensor fabrication without deep etching

A novel approach to achieving an all-SiC pressure sensor for harsh environment applications has been proposed. A combination of short-time etching, wafer thinning and wafer bonding processes is employed to form a sealed vacuum cavity structure in order to avoid an undesirable deep etching process. To demonstrate its feasibility, the thinning of SiC wafer and the bonding between a SiC patterned wafer and a bare wafer have been attempted. The SiC wafer could be thinned down to 60 μm in thickness via bonding to a Si wafer for support, and the patterned SiC wafer could be successfully bonded to a bare SiC wafer with a seamless interface, which indicates the feasibility of this approach.