Patent attributes
In a mass flow controller verifying system, there are provided a verifying gas line arranged in parallel to influent flow gas lines and joined into a post-confluent flow gas line, a reference volume calculating portion adapted to calculate a reference volume determined for a specified piping of a gas piping system, a verifying parameter calculating portion adapted to calculate a verifying parameter based on time series data of a measurement pressure measured by a pressure measurement unit during a control of a flow rate by a mass flow controller to be verified, and a comparing portion adapted to compare a reference parameter set based on the reference volume and the verifying parameter, whereby the verifying system can be introduced into an existing gas piping system used in a semiconductor manufacturing process and so forth at a low cost and is capable of verifying a mass flow controller quickly and accurately.