超声振动辅助单晶硅划片的锯切力研究

Study of sawing force in ultrasonic vibration assisted monocrystalline silicon dicing

采用金刚石超薄锯片对单晶硅划片的工艺会在划片时产生较大锯切力,从而导致较大的崩边损伤。而旋转超声辅助加工由于超声振动的作用可以减小加工时所产的切削力,同时获得较好的加工精度,越来越广泛地应用于硬脆材料的加工中。为了验证超声辅助对单晶硅划片中锯切力的作用,在实验中将超声振动添加到锯片上,使其产生径向的振动来完成对单晶硅的划片。并通过对比有超声振动辅助与无超声振动辅助的单晶硅划片的锯切力,对超声振动辅助划片中锯切力的特点进行分析。实验结果表明,超声辅助划片所产生的锯切力比无超声辅助划片所产生的锯切力小,说明超声振动的添加可以降低锯切力。同时在超声划片中产生的崩边要小于非超声加工条件下的崩边情况,说明超声振动降低锯切力可抑制硅片的崩边。

In the monocrystalline silicon dicing process with ultra-thin diamond blade, a bigger sawing force can be generated, which leads to a big chipping damage. The rotary ultrasonic assisted machining with ultrasonic vibration can reduce curing force in processing and obtain good machining precision. Thus this machining method has been more and more widely used in hard brittle materials processing. In order to reduce the sawing force in monocrystalline silicon di- cing process, ultrasonic vibration is applied to the saw blade, which makes the blade having a radial vibration, to com- plete the dicing of monocrystalline silicon. The characteristics of ultrasonic sawing force are analyzed through the comparison of sawing force between ultrasonic dicing and non-ultrasonic dicing. The experimental results show that the sawing force generated by the ultrasonic assisted dicing is smaller than that by the non-ultrasonic dicing, and so is the chapping damage. It indicates that chipping of silicon wafer can be inhibited by the smaller force generated in ultrasonic machining.