A review of calibration standards, devices and methods for gas flow in semiconductor manufacturing processes

Semiconductor manufacturing involves various gases in about 500 processes of oxidation, vapor deposition, lithography, etching doping, inerting, annealing, and chamber cleaning. To ensure the quality of manufactured semiconductors, accurate and reproducible gas flow measurement and control are necessary. Gas flow standards with low uncertainty are the foundation of accurate gas flow measurements and traceability for flow meters and mass flow controllers used in semiconductor manufacturing. Besides, physical models are significant to calculate or correct the measured flow rate and extrapolate calibration results to unknown gases introduced into the manufacturing process. Thus, in this work the intention is to provide the principles, structures and performances of gas flow standards used for calibration of process gases and corresponding models and methods for gas flow calculation and corrections. The aim is to provide some advice on measurement and calibration of gas flow in semiconductor manufacturing processes.