作者: Qing Liang Zhao, D.J. Stephenson, John Corbett, J. Hedge, J.H. Wang, Ying Chun Liang
107
作者: Hong Tsu Young, Hung Yi Huang, Ying Jay Yang
摘要: The advantages of ductile regime grinding of silicon wafer such as smooth surface
roughness (Ra < 10 nm) and minimum subsurface damage layer (< 10μm) have great impact on the production process of wafer. With ductile regime grinding, the subsequent processes such as etching and rough polishing processes can be minimized. To achieve ductile regime grinding, a fundamental concept is the application of grain depth of cut being less than the critical cut depth, dc, of the silicon wafer. However, dc is dependent on material properties, cutting conditions, and crystallographic orientation [1].The objective of this paper is to derive, and to investigate by experiment, the dc value for silicon wafer grinding. Following these key steps, the effects of dc on various major grinding parameters are studied.
253
作者: Feng Wei Huo, Zhu Ji Jin, Ren Ke Kang, Dong Ming Guo
摘要: A new non-destructive method was developed to identify the grinding mode of silicon
wafers, which is based on the information of subsurface cracks extracted from the surface
topography of the ground silicon wafers measured with a 3D surface profiler. We examined
extensive measurement data of the surface topography of silicon wafers processed by single grain
grinding or real grinding operation, and our results show that the information about median cracks
could be captured if the lateral sampling interval of the 3D surface profiler is small enough, even if
the grain depth of cut is below 20nm. If the maximum valley of the measured surface topography is
approximately equal to the grain depth of cut, surface formation will be under ductile mode,
whereas, if the maximum valley is several times larger than the grain depth of cut, surface
formation will be under brittle mode. According to this criterion, silicon wafers ground by ductile
mode or brittle mode could be identified rapidly and conveniently. Experimental validation shows
that this method is accurate.
255
作者: Yan Wu, Bo Zhao, Xun Sheng Zhu
摘要: Based on impulse theories and indentation fracture mechanics, the motion model of the contact between abrasive particle and workpiece in workpiece two-dimension ultrasonic vibration grinding (WTDUVG) was analyzed, and the critical condition of ultrasonic vibration grinding brittle-ductile transition was analyzed theoretically, furthermore the critical cutting depths of a grain under different grinding conditions were obtained by Matlab programs. In this work, the ultrasonic vibration and conventional diamond grinding of Al2O3/ZrO2 nanoceramics were performed in order to investigate the effect of workpiece ultrasonic vibration on the brittle-ductile transition mechanism, the effect of grit size, worktable speed and grinding depth on the critical depth of cut were studied by grinding experiments. the micro-topography of the grinding surface was observed by AFM and SEM. Experiment indicated that only when the grinding depth less than critical grinding depth, ductile regime grinding of ceramics can be realized, the appropriate grinding parameter on surface finish are suggested.
477
作者: Yu Fei Gao, Pei Qi Ge
摘要: Based on reciprocating electroplated diamond wire saw (REDWS) slicing experiments, a study on REDWS machining brittle-ductile transition of single crystal silicon was introduced. The machined surfaces and chips were observed by using Scanning Electron Microscope (SEM), and some experimental evidences of the change of material removal mode had been obtained. The experimental results indicate there is a close relationship between material removal mode and the ratio r value of ingot feed speed and wire speed, through controlling and adjusting the r value, the material removal mode can be complete brittle, partial ductile and near-ductile removal.
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