An XRD Phase Analysis of Al-F Re-Deposition Produced from Reactive Ion Etching

Abstract

This paper reports the analysis of the composition, structure and phase of the re-deposition material that was generated from the reaction from CF4 plasma etching on the Al2O3-TiC substrate. The re-deposition was sputtered from the etching area and deposited on a silicon coupon for analysis. The morphology of the re-deposition was investigated by scanning electron microscope (SEM) and the composite element of the re-deposition was detected by using energy dispersive x-ray spectroscopy (SEM-EDX). X-ray diffraction (XRD) was used to analyse the structure and phase of the re-deposition. The results show that the prepared re-deposition was composed of F and Al atoms, with 51.24 At% and 27.67 At%, respectively. XRD revealed that this was owing to the chemical formula AlF3, which has a rhombohedral crystal structure in the most stable alpha phase (α-AlF3).