Applied Materials, Inc.
Methods, systems, and apparatus for mass flow verification based on rate of pressure decay

Abstract:

Mass flow verification systems and apparatus verify mass flow rates of mass flow controllers (MFCs) based on pressure decay principles. Embodiments include a location for coupling a calibrated gas flow standard or a MFC to be tested in a line to receive a gas flow from a gas supply; a control volume serially coupled to the location in the line to receive the gas flow; a flow restrictor serially coupled to the control volume; a pump serially coupled to the flow restrictor; and a controller adapted to allow the gas supply to flow gas through the mass flow control verification system to achieve a stable pressure in the control volume, terminate the gas flow from the gas supply, and measure a rate of pressure decay in the control volume over time. Numerous additional aspects are disclosed.