Analysis of contact length and temperature effect in rocking mode diamond wire sawing of monocrystalline silicon carbide wafer

Abstract

Diamond wire sawing (DWS) is a primary and fundamental stage for slicing large-diameter ingots into multiple wafers, enabling high-volume production in a single process. However, the extended contact length between the diamond wire and work material generates heat, which detrimentally impacts the surface quality of the sliced wafers and accelerates the diamond wire wear rate. This study implemented a rocking mode sawing strategy to investigate the effect of contact length on the surface quality of as-sawn wafer and diamond wire wear rate. Experiments have been conducted on monocrystalline silicon carbide (4H-SiC) with and without a rocking-mode multi-DWS machine. The experimental sawing temperature has been validated using Fourier’s law of thermal conduction, a finite element model, and a linear time series regression model. Results indicated that the minimal sawing temperature had been observed with the rocking mode sawing strategy, attributed to its shorter contact length compared to the process without rocking mode. Additionally, the finite element and regression models closely matched the experimental data, achieving accuracies of 93.57 % and 99.96 %, respectively. Fourier’s law of thermal conduction proved significant for precisely determining the sawing temperature. Notably, the rocking mode sawing strategy significantly affected the sawing temperature, surface quality, and diamond wire wear rate compared with the sawing process without the rocking mode.