单晶硅片磨削表面相变研究

为了揭示硅片自旋转磨削加工过程中材料的去除机理，采用显微拉曼光谱仪研究了硅片磨削表面的相变。结果表明：半精磨和精磨硅片表面存在-Si相、Si-III相、Si-IV相和Si-XII相，这表明磨削过程中Si-I相发生了高压金属相变（Si-II相），Si-II相容易以塑性方式去除。粗磨硅片表面没有明显的多晶硅，只有少量的非晶硅出现，材料以脆性断裂方式去除。从粗磨到精磨，材料去除方式由脆性断裂去除向塑性去除过渡。粗磨向半精磨过渡时，相变强度越大，材料的塑性去除程度越大；半精磨向精磨过渡时，相变强度越小，材料的塑性去除程度越大。

Study on the Phase Transformations of the Ground Monocrystalline Silicon Wafers Surfaces

In order to understand the material removal mechanism during wafer rotation grinding,the phase transformations on the ground silicon wafer surface were investigated by Raman microspectroscopy.The results existing the amorphous silicon(α-Si),Si-Ⅲ phase,Si-Ⅳ phase and Si-Ⅻ phase on the semi-fine and fine ground wafer surfaces indicate that the Si-Ⅰ phase has been transformed into ductile metal phase(Si-II phase) during grinding,and the Si-Ⅱ phase is ductile and easily be removed by ductile mode.There is no obvious polycrystalline silicon on the rough ground wafer surface,but very small amounts of α-Si is observed,these materials are removed by brittle mode.From rough grinding to fine grinding,the material removal mode changes from micro-fracture mode to ductile mode gradually.During the transition from rough grinding to semi-fine grinding,the ductile mode removal degree increases with the increasing phase transformation degree;the transition from semi-fine grinding to fine grinding,the ductile mode removal degree increases with the decreasing phase transformation degree.