Improved reliability of breakdown voltage measurement of yttrium oxide coatings by plasma spray

Abstract

Understanding the dielectric breakdown voltage of coatings inside plasma equipment is important for improving the reliability of semiconductor processes. Measurements of breakdown voltage can vary owing to many factors, but the measurement itself has not yet been studied systematically. In this paper, we designed two type tools to measure the breakdown voltage. We decided to use a one-electrode method with a 20 mm(2) electrode and chose to apply the voltage at 15 V/s to minimise measurement error. We used these tools to systematically evaluate the breakdown voltages of different coatings deposited using various methods. Coatings deposited using suspension plasma spraying had a higher breakdown voltage than coatings deposited using atmospheric plasma spraying, because suspension plasma spraying films can be deposited at high density, minimizing electrical stress. As the fluorine content in the coating increased, it is widely used for material of excellent etching resistance in fluorine plasma etching. However, dielectric breakdown voltage decreased with increasing fluorine content, which could affect process reliability.