Abstract: A wafer processing technique separates an extremely thin wafer into a plurality of completed circuit-containing dice without having to directly handle the wafer. In one embodiment, a substrate is thinned by forming a trench pattern in its top surface, the trench depth being the intended thickness of the die. A polishing resistant material is then formed in the trench and planarized down to a topside passivating layer, which is patterned to expose surface test regions. After wafer-probe testing, the wafer is affixed face-down on a support handle by means of an adhesion material such as wax. The substrate is backside-lapped down to the stop material in the trench, leaving a thin wafer layer. After the trench material is removed. Individual dice are separated from the support handle by melting the wax. In a further embodiment, a thin wafer layer if formed on a buried oxide layer. After trench patterning and face-down wax-mounting, the support substrate is polished down to the buried insulator layer.