Temperature-Dependent ALD and Quasi-ALE Behavior of Ruthenium Thin Films

The precise control of deposition and etching processes is essential for integrating Ruthenium (Ru) as a potential copper (Cu) replacement in advanced interconnect technology. In this study, atomic layer deposition (ALD) Ru films were deposited at various temperatures, and their etching behavior in quasi-atomic layer etching (ALE) was investigated. The quasi-ALE process was conducted through adsorption (oxidation), desorption (removal), and reduction steps to achieve controlled Ru etching. The relationship between deposition conditions and etching characteristics was analyzed to understand the quasi-self-limiting behavior of the process. This study provides insights into optimizing oxidation and reduction conditions for a more stable and uniform ALE process, contributing to the development of Ru-based interconnects.