Study of an on-line precision microgroove generating process on silicon wafer using a developed ultra-thin diamond wheel-tool

This study presents a novel and economical method for precisely developing an ultra-thin diamond grinding wheel-tool and using the finished wheel-tool to on-line fabricate crisscross microgrooves on silicon wafer. The wheel-tool blank is made of diamond grain of 0-2 μm grade via a designed micro co-deposition. A non-continuous cathode design, in which current crowding effect can be suppressed, is used to obtain a diamond wheel-tool with good surface characteristics. With abrasive content of 8 g/l, a suitable interval chip-pocket of 2-3 μm can be generated. The grinding wheel blank is thinned and dressed simultaneously down to a thickness of 15 μm using micro wire Electro Discharge Dressing (w-EDD). The finished wheel-tool is directly utilized to grind the crisscross microgrooves on the silicon wafer using 'high-speed and fast-shallow grinding' technique. A grinding depth of 0.5 μm per stroke is exactly controlled to ensure that the removal mechanism transfers to a ductile grinding mode. The width, depth and surface roughness R_a of the microgrooves are 15 μm, 9 μm and 0.087 μm, respectively.