Patent · US Active

Methods for performing actual flow verification

US7822570B2 · kind B2 · utility

6Cited by
12References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 9, 2007
Grant dateOct 26, 2010
Priority date
Expiry dateMay 15, 2028

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7722
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method for determining an actual gas flow rate in a reaction chamber of a plasma processing system is provided. The method includes delivering gas by a gas flow delivery system controlled by a mass flow controller (MFC) to an orifice, which is located upstream from the reaction chamber. The method also includes pressurizing the gas to create a choked flow condition within the orifice. The method further includes measuring a set of upstream pressure values of the gas via a set of pressure sensors. The method yet also includes applying a calibration factor of a set of calibration factors to determine the actual flow rate. The calibration factor is a ratio of an average of the set of upstream pressure values to an average of a set of golden upstream pressure values, which is associated with an indicated flow rate for an MFC.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.