Anthony Lee Pearson

US Patent:

56205244, Apr 15, 1997

Filed:

Feb 27, 1995

Appl. No.:

8/395613

Inventors:

Chiko Fan - Danville CA
Anthony Pearson - San Jose CA
J. James Chen - Campbell CA
James L. White - Half Moon Bay CA

International Classification:

C23C 1600

US Classification:

118726

Abstract:

Described herein is an apparatus and method for delivering fluid components for semiconductor processes such as chemical vapor deposition (CVD) and chemical etch processes. Any prescribed mixture of separate fluid reagents can be delivered with extreme accuracy and precision using the apparatus we describe here. The unique embodiment of a precision fluid pumping system utilizing internal pressure and temperature transducers, capacity volume and restrictive elements that comprise a continuous pulse-free system for use in CVD applications. This system has superior performance characteristics in the areas of: accuracy, precision, repeatability of the fluid mixture delivery and continuous repeatable delivery without intermittent pulsation. We describe a novel fluid pump whose design is integrated using a closed loop feedback system composed of temperature and pressure sensors. This allows the entire system to perform to in either an isobaric-isothermal mode or an isocratic-isothermal mode.

US Patent:

50605070, Oct 29, 1991

Filed:

Jun 21, 1989

Appl. No.:

7/369104

Inventors:

John Urmson - Oakland CA
Anthony Pearson - Watsonville CA
Sanjay Gidwani - Fremont CA

International Classification:

G01N 2918

US Classification:

73 2401

Abstract:

A method and apparatus for fluid mixture monitoring and controlling using an acoustic sensing technique by pulsing a fluid sample and a reference fluid in elongated chambers with sound waves generated at one end of the chambers and sensing the resonant frequencies in the chambers, or the time lapse for the sound waves to traverse the chambers, with transducers disposed proximate the other ends of the chambers and ratiometrically comparing the time-based measurements.