SEMI F54 - Test Method for Measuring the Counting Efficiency of Condensation Nucleus Counters
This Standard was technically approved by the Gases Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on August 18, 2017. Available at www.semiviews.org and www.semi.org in April 2018; originally published June 2000; previously published November 2010.
Particle specifications for gases require the use of condensation nucleus counters (CNCs) having specified counting efficiencies. This Document provides the test method for determining the counting efficiencies of CNCs.
This Document provides the method for (1) generating an aerosol standard consisting of sodium chloride (NaCl) particles having sizes 0.01 micrometer and larger suspended in air at atmospheric pressure (1 × 105 Pa), (2) controlling the size and concentration of particles in the aerosol, and (3) using the aerosol to determine the counting efficiency of a CNC as a function of particle size. This method is suitable for CNCs having a lower size sensitivity of 0.01 micrometer or larger.
Referenced SEMI Standards