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Article: If its ain't broke, don't replace it. (mass flow controllers)
- Article from:
- R & D
- Article date:
- September 1, 1997
- Author:
CopyrightCOPYRIGHT 1997 Advantage Business Media. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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In the 1993 training manual "Mass Flow Control in a Semiconductor Process," Sematech, Austin, Texas, reported that 70% of mass flow controllers (MFCs) replaced by semiconductor fabs were later found to work perfectly. While results vary from study to study and industry to industry, it's clear that too many MFCs are being replaced needlessly, because of misdiagnosed gas-flow problems that masquerade as MFC failures but lie elsewhere in the gas delivery system. Understanding how a MFC works can help fix blame where it belongs.
Mass flow meter operation A mass flow controller consists of a mass flow meter (MFM) and a flow controller. While most of the incoming gas ...