Spray etch dicing method

摘要

A method is disclosed for dicing individual or groups of diode mesas fabricated upon a single metal heat sink. The undiced device is placed diode mesas down upon a transparent glass plate with the mesas protected in wax. A first mask is positioned upon the opposite side of the plate by alignment with the diode mesas as seen through the plate. Portions of the first mask extend on the plate beyond the edges of the wax and heat sink. A second etching mask is then fabricated upon the bottom of the heat sink by exposing a layer of photoresist through a mask having the same grid pattern as the first mask and which is aligned with the portions of the first mask seen through the glass plate beyond the edge of the heat sink. The diode mesas are etched apart by spraying an appropriate etchant through apertures in the etching mask.