The Effects of Strong Oxidizing Slurry and Processing Atmosphere on Double-Sided CMP of SiC Wafer

Abstract

In order to achieve high removal rate and high-quality processing on SiC wafer, we carried out the CMP processing experiment with the new type CMP machine (Bell-jar) by using the slurry with the addition of strong oxidant (KMnO 4 ). It was found that the high speed CMP processing was achieved by controlling the concentration of KMnO 4 in the slurry, the pH of slurry and the processing atmosphere. By using the slurry with the addition of KMnO 4 of 0.1mol/L, the removal rate was the fastest up to 1019nm/h in the fixed pH of 6. By use of the slurry of pH 3, the removal rate of C-face of SiC wafer was 1695nm/h On the other hand, the fastest removal rate of Si-face of SiC wafer was only 51nm/h by using the slurry whose pH is 7. In the open air atmosphere, the removal rate was 915nm/h, which was higher than that at the higher and lower atmospheric pressure.