Peter B Read

US Patent:

56518340, Jul 29, 1997

Filed:

Aug 30, 1995

Appl. No.:

8/521495

Inventors:

Min-Chung Jon - Princeton Junction NJ
Hugh Nicholl - Berthoud CO
Peter Hartpence Read - Morrisville PA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

B08B 500

US Classification:

134 31

Abstract:

An object (12) may be cleaned by CO. sub. 2 reduced ESD by directing a first water mist (23) at a surface (14) of the object while imparting a relative motion between the object board and the mist to form a film of water on the object surface. As the relative motion is imparted between the board and the first mist (23), a second water mist (32) is injected into a stream (30) of solid CO. sub. 2 particles (27) directed at the object surface downstream of the first mist. Water droplets in the second mist in the second mist combine with the CO. sub. 2 particles to create carbonic acid that disassociates into charged ions that increase the conductivity of the water film, allowing for increased charge dissipation, thus reducing the incidence of ESD.

US Patent:

61030163, Aug 15, 2000

Filed:

Nov 28, 1995

Appl. No.:

8/562619

Inventors:

Min-Chung Jon - Princeton Junction NJ
Hugh Nicholl - Berthoud CO
Peter Hartpence Read - Morrisville PA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

C03C 2300

US Classification:

134 2

Abstract:

Electrostatic discharges that occur during solid CO. sub. 2 cleaning of a substrate (10) can be virtually eliminated by chilling the substrate so that moisture in the atmosphere, in the form of water droplets(30), condense on the substrate surface (14), thereby forming a continuous film of water (28). The water in the film (28) reacts with the solid CO. sub. 2 (24) to form carbonic acid that dissociates into free ions that neutralize the charge on the solid CO. sub. 2.