Patent · US Expired

Ultra-high efficiency porous metal filter

US5114447A · kind A · utility

75Cited by
15References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 12, 1991
Grant dateMay 19, 1992
Priority date
Expiry dateMar 12, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22F3/1103
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An ultra-high efficiency particulate air filter for use in the microelectronics manufacturing industry is formed as a fully homogeneous sintered metal filter that exhibits an efficiency substantially in excess of a 6 log reduction and preferably equal to or exceeding a 9 log reduction (an efficiency of 99.9999999%). The filter can be used as a process gas in-line filter in state of the art gas supply systems. The porous metal filter exhibits long term stability relative to mechanical or thermal stress and operates within the desired ultra-high efficiency levels even under high pressure conditions. It does not exhibit an outgassing problem and there is no particle shedding. These features are provided within a unit no larger than those conventionally employed heretofore with organic membranes and under substantially identical operating conditions.

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