Temporary and permanent wafer bonding for reliable backside processing of compound semiconductor wafers

摘要

This paper presents two wafer bonding methods used for Ⅲ -Ⅴ compound semiconductors processing. First method describes the use of aligned reversible wafer bonding of a device wafer to a rigid carrier wafer by wax intermediate layer for optimum handling. After backside thinning and processing the device wafer is easily debonded. This procedure enables a secure handling of brittle wafers. The second method is used for Si/GaAs heterostructures fabrication by a low temperature direct wafer bonding method which uses spin-on glass (SOG) intermediate layers. The processing temperatures are lower than 200°C. The achieved bonding energy (2 J/m~2) allows thinning down of GaAs wafers to a few microns using grinding followed by chemical mechanical polishing. After thinning, the heterostructures sustained annealing temperatures of 450°C without damaging of the bonded interface.