High-Efficiency Slicing of Silicon Ingot by Flat Wire-EDM

摘要

As the solar industry requires the cutting of silicon ingots into blocks and into wafers, the slicing across large area at high machining rate while avoiding kerf loss is a main issue. The wire electrical discharge machining (WEDM) without mechanical force has been introduced. However, the conventional WEDM method cannot meet the above requirement satisfactorily for slicing silicon due to the limited capacity of wire in carrying both high electrical current and mechanical tension. The improvements of a new type wire electrode were explored and experimentally evaluated in this study for the machining of 156 mm square ingot of polycrystalline silicon. The machining rate of 343 mm~2/min, 2-3 times higher beyond the current technologies, can be achieved.