79 / 2024-09-27 15:12:12

Etching resistance of yttrium oxyfluoride coatings deposited by RF-MS under fluorocarbon plasma

YOF, RF-MS, Fluorocarbon plasma, Etching

The rapid advancement of the semiconductor industry has positioned dry etching as a pivotal technology in large-scale integrated circuit manufacturing. Typically, fluorocarbon plasma is employed for high-speed vertical wafer etching. However, during this process, plasma can cause corrosion within the etching chamber, thereby shortening the service life of the equipment. At the same time, etching byproducts may fall off from the inner chamber walls as suspended particles, resulting in silicon wafer contamination. Therefore, a protective plasma etching-resistant coating is applied to the inner surface of the chamber to effectively mitigate etching damage. Yttrium oxyfluoride (YOF) emerges as a promising replacement for yttrium oxide (Y2O3) and yttrium fluoride (YF3) coatings, aiming to suppress particle pollution and process drift. This study successfully deposited hexagonal YOF coatings with high purity and density by radio frequency magnetron sputtering system (RF-MS). Using CF4+O2 as the etching gas, YOF was subjected to physical etching, whereas Al2O3, Y2O3, and YF3 were subjected to both physical and chemical etching. The composition and thickness of the polymer layer formed during chemical etching played a pivotal role in the etching process. With the increase in the etching duration, the etching resistance of the YOF coating was enhanced, suggesting its potential as a novel protective material for etcher chamber components.