Fabrication and Characterization of Gel-Forming Cr₂O₃ Abrasive Tools for Sapphire Substrate Polishing

Abstract

This paper proposes a gel-formed abrasive tool to address the problem of abrasive agglomeration in a traditional hot-pressing abrasive tool. The effect of Polyimide resin content on the mechanical properties of the gel abrasive tools were tested, and a comparison of the mechanical properties of the gel abrasive tool and the hot-pressing tool was conducted. An orthogonal experiment was conducted to explore the best combination of machining parameters. A polishing experiment of sapphire was conducted to compare the processing effect of the gel abrasive tool and hot-pressing tool. The results from testing the mechanical properties showed that the tensile, flexural, and impact strength of the gel abrasive tool was better than that of the hot-pressing abrasive tool. The results of the orthogonal experiment showed that the best process parameters of the gel abrasive tool were a spindle speed of 900 rpm, a feed rate of 8 μm/min, and a grinding depth of 16 μm. The polishing experiment showed that the gel abrasive tool had a better processing effect on sapphire. The sapphire surface processed by the gel abrasive tool had no deep scratches, and an ultrasmooth surface could be obtained after chemical mechanical polishing (CMP).

Keywords

• polyacrylamide gel
• polyimide resin
• Cr₂O₃ abrasives
• sapphire substrate
• surface roughness