| 摘要 |
<p>A method for calculating an excess flow rate of a flowed process gas includes: flowing process gas into a chamber having a known volume through a mass flow controller; and measuring successive data sample points, which include pressure data, temperature data, and a time value for each successive data sample point. Groups of successive data sample points are identified, in which each group shares one or more successive data sample points with another group, and ratio values are calculated for each of the successive data sample points, in which each ratio value is a ratio between the pressure data and a product of temperature and gas compressibility data for each respective time value. A line of best fit of the ratio values is determined within at least one group, and then the excess flow rate of the flowed process gas is calculated through a pressure rise rate technique, in which the pressure rise rate technique utilizes a ratio value determined from the line of best fit for at least one time value within the at least one group.</p> |
