A method of fabricating thermal ink jet printheads comprises aligning and bonding a pair of silicon wafers together, which have, on opposing confronting surface thereof, a plurality of sets of linear arrays of heating elements and associated driver circuitry on one wafer surface and a plurality of sets of parallel grooves and a communicating reservoir for each set of grooves. The grooves and reservoirs are filled with a filler material which is solid or gels at room temperature and liquid at higher temperatures. The bonded pair of wafers are severed into a plurality of individual printhead sby dicing processes conducted at room temperature. One of the dicing processes cuts the grooves in a direction perpendicular thereto in order to form concurrently the nozzle face and nozzles. The solid filler material supports fragile edges of the wafers and prevents entry of dicing debris and other contaminants. The printheads are subjected to heat, spinning, and high pressure water spray to remove the filler material.