The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 07, 1999
Filed:
Nov. 17, 1995
Applicant:
Inventors:
Peter M Hammond, Rochester, NY (US);
Kevin J Kearney, Fairport, NY (US);
Assignee:
Lightforce Technology, Inc., Rochester, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438115 ; 438120 ; 438906 ;
Abstract
A process for detachment and removal of microscopic contaminant particles from a surface includes a pulsed detach light directed at the surface to excite a contaminant particle thereon at or near its resonant frequency, to thereby detach the particle from the surface; and a photophoresis light directed at the particle to move it by photophoresis, to thereby prevent its reattachment to the surface. A thermal gradient may also be applied to control the velocity and direction of particle movement by thermophoresis. Detach light is of variable pulse frequency and angle of incidence.