Modeling and investigation on wafer shape in wafer rotational grinding method

作者:Tang, Keyan*; Kang, Renke; Guo, Dongming; Song, Li
来源:International Journal of Advanced Manufacturing Technology, 2013, 64(5-8): 707-714.
DOI:10.1007/s00170-012-4040-4

摘要

With the fast development of the integrated circuits, the size of the wafer is getting larger and the demand for the wafer shape and flatness has become higher and higher. There are many factors which could influence the wafer shape. So in this paper based on the rotational coordinates method, a theoretical model of the ground wafer shape in wafer rotational grinding is firstly developed, in which the main factors were considered, including parameters of the dressing vacuum chuck and the wafer grinding, etc. Secondly, the simulation system was developed by Visual C++ and OpenGL according to the model, by which the simulation results of wafer shape could be made and the relationship between the wafer shape and parameters can be gotten. Finally, the experiments of wafer grinding were carried out on an ultra-precision grinder (VG401MKII), and the developed model is verified to be correct by comparing the experiment results and simulation results. The research indicates the wafer shape and flatness can be predicted exactly, and it is quite significant to choose the reasonable parameters to effectively control the wafer shape in the wafer rotational grinding. The total thickness variation can be controlled within 1 nm if the parameters are chosen reasonably.