Papers by Keyword: Fixed Abrasive

Abstract: The depth of surface/subsurface damage layer is the key index of surface quality of sapphire. In this paper, that depth model of the surface/subsurface damage lay characterized by the crack length was established according to the mechanical theory of indentation fracture. The cutting relation between abrasive and workpiece and the difference of the depth of subsurface damage crack are analyzed. It is preliminarily estimated that the length of sub-surface damage crack of free abrasive sapphire is about 2.46 times that of fixed abrasive when considering only the contact hardness of abrasive grain under static load. Diamond abrasives with size of W20 were adopted to carry out experiments in free and fixed lapping methods. The results show that the surface/subsurface damage depth is 9.87μm and 3.63μm respectively. It is easier to obtain good sub-surface quality by using the fixed abrasive method than free abrasive at the same particle size.

Abstract: The wafer grinding by use of fixed abrasive diamond wheels is required to create a high-quality wafer surface in a short time. In general, it is known that the grinding performance of diamond wheel is mainly dependent on grinding wheel specifications and grinding conditions. The cutting edge distribution or abrasive protrusion height in depth-wise of a specified wheel is one of the most important factors to determine the finishing surface roughness and the grinding force, which in turn determine the surface and subsurface quality of ground wafers. The overall purpose of this study is to understand the dynamic behavior of each diamond abrasive via modeling an actual diamond wheel and simulating of wafer grinding. In previous report [1], we have theoretically analyzed three-dimensional cutting edge distribution on the working surface of diamond wheels. This paper reports our recent achievements in the evaluation of 3-D cutting edge distribution in depth-wise of a specified wheel via the bearing ratio of its topography.

Abstract: According to the shortcomings of the traditional free abrasive chemical mechanical polishing (CMP), in recent years, the fixed abrasive chemical mechanical polishing (FA-CMP) technology is proposed. It is a new planarization technology developed on the basis of the traditional CMP. Pad is an important and dispensable part in FA-CMP. The cost and quality of FA-CMP pad are determined by the preparation technology. In order to study the FA-CMP pad of the low cost and high quality, in this paper, by reading a lot of literature, 5 kinds of preparation technology of FA-CMP pad are analyzed. Study results will provide some reference for further designing and manufacturing the FA-CMP pad.