SEMI F38 - Test Method for Efficiency Qualification of Point-of-Use Gas Filters
This Standard was technically approved by the global Gases Committee. This edition was approved for publication by the global Audits & Reviews Subcommittee on May 13, 2011. Available at www.semiviews.org and www.semi.org in June 2011; originally published June 1999; previously published November 2004.
NOTICE: This document was reapproved with minor editorial changes.
The purpose of this document is to define a comprehensive standard test sequence to qualify the particle filtration efficiency achievable using point-of-use (POU) gas filters.
This test method defines an evaluation method for POU filters of various media (e.g., metallic, ceramic, and polymeric) typically used for filtering inert and process gases in semiconductor applications. POU filters are designed to handle relatively low flow rates (0.5 to 50 slm) and moderately high pressure drops. The filter housing and filtration element are combined into one sealed and inseparable unit.
This test method is intended to demonstrate the ability of a POU gas filter to equal or exceed a specific particle filtration efficiency class when challenged with a monodispersed aerosol in the size range described in § 6.6.
The efficiency class of the test method is defined as the log reduction value (LRV), where LRV is the Log [Input Concentration/System Background Level].
Referenced SEMI Standards