二维超声振动辅助化学机械磨削技术及单晶硅实验

Two Dimensional Ultrasonic Vibration Assisted Chemical Mechanical Grinding and Experiment on Si Wafer

为了提高材料去除率和加工通用性,本文提出了工具施加二维超声波振动辅助的化学机械磨削(CMG)复合加工方式,开发具有伸缩和弯曲两种模态的二维超声波振动子及实验装置.以单晶硅片为加工对象,进行单点切削加工轨迹特性分析,并比较不同加工模式以及加工参数对表面粗糙度和材料去除率的影响.实验结果表明,二维超声辅助下的单点切削轨迹存在更多延性加工趋势.在同样普通机床精度条件下,随着时间的增加,二维超声辅助CMG表面粗糙度明显改善,达到纳米级.较无超声情况下二维超声波辅助CMG复合加工材料去除率提高约1倍,可获得最优表面粗糙度5 nm,一维径向超声辅助加工结果次之.

To improve material remowd rate and machining popularity, two dimensional ultrasonic vibra- tion assisted chemical mechanical grinding （CMG） was introduced in this paper as the combined grinding method. And two dimensional vibrators with longitudinal and bending modes and integrated experimental installation were developed. Si wafer was taken as machining material, and the experiments were carried out to examine the characteristic of machining locus using single point cutting, and the influence of different machining modes and parameters on surface roughness and material removal rate. The results show that two dimensional ultrasonic assisted single point cutting locus makes more ductile removal. When using the general-purpose machine, two dimensional ultrasonic assisted CMG can obtain better surface roughness at nanometer level as the machining time increases. Compared with conventional CMG without ultrasonic vibration the material removal rate improves by 100% and the best surface roughness is 5 nm. Two dimensional ultrasonic assisted CMG yields the best surface roughness and the largest material removal rate, and one dimensional radial ultrasonic assisted CMG is relatively backward.