Patent · US Expired

Method for rapidly determining an impurity level in a gas source or a gas distribution system

US5714678A · kind A · utility

4Cited by
23References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 26, 1996
Grant dateFeb 3, 1998
Priority date
Expiry dateNov 26, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N33/0004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Provided is a novel method for rapidly determining an impurity level in a gas source. A gas source and a measurement tool are provided for measuring an impurity level in a gas flowing from the gas source. The measurement tool is in communication with the gas source through a sampling line. The sampling line has a gas inlet disposed upstream from a gas outlet. The sampling line is baked according to a baking strategy, such that when baking is terminated, a concentration profile of the impurity in the sampling line contains a first region and a second region. In the first region, extending from the gas inlet to a point downstream from the inlet, the vapor phase concentration of the impurity is less than the vapor phase concentration of the impurity in the gas entering the sampling line. In the second region, located downstream from the first region and extending to the gas outlet, the vapor phase concentration of the impurity is greater than the vapor phase concentration of the impurity in the gas entering the sampling line. A method for rapidly determining an impurity level in a gas distribution system which delivers gas to a point of use is also provided. Particular applicability i…

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