TEOS Integrated High-Low Pressure RPS Clean: APC: Advanced Process Control

Current clean recipe settings utilize high-pressure values referencing best-known methods (BKM) for remote plasma chamber NF3 cleaning. In this paper, a novel cleaning recipe integrating high and low pressure values is demonstrated. The working mechanism of this improved cleaning is explained through the concept of mean free path, where the addition of a lower pressure cleaning step enables ionized fluorine radicals to travel longer before collision and covering a wider area, serving as a complement to high pressure cleaning. This novel chamber cleaning procedure with two consecutive clean steps: initial high pressure step followed by a low pressure step has been evaluated in an industrial PECVD chamber, showing up to 60% reduction in particle counts, 8.5% reduction in Ar and NF3 usage and gas cost savings.