Process gas delivery system for CVD having a cleaning subsystem

摘要

A process gas delivery system incorporating a cleaning solution delivery subsystem for chemical vapor deposition. The system includes a slanted cleaning solution feed pipe for introducing a cleaning solution into the process gas delivery system and for disposal of waste cleaning solution from the process gas delivery system. Automatic determination of maintenance time may be accomplished by using an optical sensor provided on the process gas delivery pipe that detects the accumulation of the deposition material within the piping. The sensor may also be used to detect the cleaning solution residue inside the piping after cleaning and the liquid level during deposition.