Plasma Erosion Resistance and Microstructure of Yttrium Oxide and Yttrium Fluoride Films by Vacuum Kinetic Spray (VKS)

During the semiconductor etching process, halogen plasma causes damage to the equipment surface and generation of contaminating particles. These problems cause the semiconductor fabrication process to be inefficient. In this study, Y₂O₃, and YF₃ films were deposited on aluminum substrate through the vacuum kinetic spray (VKS). Through the VKS process, a dense ceramic film could be readily formed by impacting of the accelerated particle on the substrate. High-density ceramic films have been reported to be superior in terms of plasma resistance. To evaluate the films performance, field emission scanning electron microscope (FE-SEM) and inductively coupled plasma (ICP) type etching system was used to analyze the microstructure of the coating and plasma erosion resistance. Dense films of several micrometers in thickness was successfully formed. The etch rate of the films was as small as several tens of nm/h and the roughness slightly increased. As a result, it was possible to dramatically improve the plasma erosion resistance of metallic substrate by fabrication of Y₂O₃ and YF₃ coatings via VKS process.

Keywords: Vacuum Kinetic Spray (VKS); Plasma erosion resistance; Yttrium ceramic; Microstructure