Free Abrasive Machining in Slicing Brittle Materials With Wiresaw

Abstract

Wiresaw has emerged as a leading technology in wafer preparation for microelectronics fabrication, especially in slicing large silicon wafers (diameter⩾300 mm) for both microelectronic and photovoltaic applications. Wiresaw has also been employed to slice other brittle materials such as alumina, quartz, glass, and ceramics. The manufacturing process of wiresaw is a free abrasive machining (FAM) process. Specifically, the wiresaw cuts brittle materials through the “rolling-indenting” and “scratch-indenting” processes where the materials removal is resulting from mechanical interactions between the substrate of the workpiece and loss abrasives, which are trapped between workpiece and wire. Built upon results of previous investigation in modeling of wiresaw, a model of wiresaw slicing is developed based on indentation crack as well as the influence of wire carrying the abrasives. This model is used to predict the relationship between the rate of material removal and the mechanical properties of the workpiece together with the process parameters. The rolling, indenting, and scratching modes of materials removal are considered with a simple stochastic approach. The model provides us with the basis for improving the efficiency of the wiresaw manufacturing process based on the process parameters.