Hard substrate wafer sawing process

摘要

Die of high aspect ratio formed in a hard wafer substrate are sawed out without requiring tape, obtaining high die yields. Preliminary to sawing the semiconductor die ( 3 ) from a sapphire wafer ( 2 ), the wafer is joined ( 20 ) to a silicon carrier substrate ( 6 ) by a thermoplastic layer ( 4 ) forming a unitary sandwich-like assembly. Sawing the die from the wafer follows. The thermoplastic is removed, and the die may be removed individually ( 50 ) from the silicon carrier substrate. Thermoplastic produces a bond that holds the die in place against the shear force exerted by the saw and by the stream of coolant ( 30 ).