Dry Strip Removal of Si-Containing Anti-Reflective Coating Photo Resist Stacks

Removal of SiARC containing photo resist stacks presents significant challenges to conventional plasma dry strip tools. Due to the high Si content (35-45% Si), the SiARC removal process must typically be done with a combination of dry and wet processes or done entirely in an etcher. As both the Dry-Wet-Dry and the Etcher approach to SiARC stack removal are long and high cost processes, a single chamber, dry-only solution to SiARC stack removal is highly desirable. This paper reports the dry strip process developed at Axcelis Technologies, Inc. to remove the SiARC stack layer by layer which results in a residue free oxide substrate.