Non-Destructive Characteristics Evaluation for Low Vacuum Dry Pumps in the Semi-Conductor Manufacturing Process Line

Since positive-displacement dry vacuum pumps were first launched into the semiconductor industry in 1984, issues concerning about characteristics evaluation on consistent bases have been continuously arisen from the mass production lines. The non-destructive, in-situ purposed characteristics evaluation system for dry vacuum pumps has been established collaborating with a semi-conductor manufacturer and branch dry pump manufacturers in Korea. The evaluation method exploits the constant volume flow meter to measure the mass flow rate in standards level, and facilitates the evaluation of spatially averaged sound power levels using a semi-anechoic chamber. New and overhauled roots and claw type pumps have been evaluated in terms of ultimate pressure, pumping speed, vibration, and sound power. The correlation analyzed among those results shows clear signs of pump degradation related each other. Recent results are applicable to the semi-conductor process line to warn early symptoms of pump degradation and malfunction.