Measuring and testing – Particle size
Patent
1989-07-14
1991-12-17
Raevis, Robert
Measuring and testing
Particle size
356 37, G01N 100
Patent
active
050726269
ABSTRACT:
A measurement system for microelectronic clean rooms to measure ultrafine particle size distribution in the range of 0.002 to 0.2 micrometers is provided which includes four screen diffusion stages each connected in series with a condensation nucleus detector. The input to each screen diffusion stage is connected to a localized area to be measured, and the output of each condensation nucleus detector is connected to a vacuum system which simultaneously draws particle bearing air through the four channels. The output signals of the condensation nucleus detectors present particle size distributiion. In one embodiment of the present invention, one or more optical particle detectors are connected in parallel with the diffusion stage-condensation nucleus detectors to expand the distribution measurements to larger sizes. Other embodiments inclulde a manifold probe to probe a localized area, an alarm system actuated when particle levels exceed a predetermined level, and a manifold assembly to minimize vacuum lines passing through the walls of the microelectronic clean room.
REFERENCES:
patent: 2353828 (1944-07-01), Hyde
patent: 3457787 (1969-07-01), Maatsch et al.
patent: 3678487 (1972-07-01), Ludewig, Jr. et al.
patent: 3709614 (1973-01-01), Hayakawa
patent: 3830688 (1974-08-01), Mannbro
patent: 3831452 (1974-08-01), Pittenger
patent: 4128335 (1978-12-01), Haberl et al.
patent: 4182632 (1980-01-01), Cargill
patent: 4449816 (1984-05-01), Kohsaka et al.
patent: 4463595 (1984-08-01), Yeh et al.
patent: 4570494 (1986-02-01), Dunn et al.
patent: 4742718 (1988-05-01), Jimbo
patent: 4764758 (1988-08-01), Skala
patent: 4790650 (1988-12-01), Keady
patent: 4792199 (1988-12-01), Borden
patent: 4860598 (1989-08-01), Bailey et al.
patent: 4890481 (1990-01-01), Ezawa et al.
Ensor David S.
Sem Gilmore J.
Freedman Irving M.
Raevis Robert
Research Triangle Institute
LandOfFree
Measurement of ultrafine particle size distributions does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Measurement of ultrafine particle size distributions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Measurement of ultrafine particle size distributions will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-829873