Donald M Stephens

US Patent:

6430841, Aug 13, 2002

Filed:

May 26, 2000

Appl. No.:

09/580825

Inventors:

Jonathan Borkowski - Sunnyvale CA
Oliver David Jones - Watsonville CA
Kenneth C. McMahon - Morgan Hill CA
Scott Petersen - Scotts Valley CA
Donald Stephens - Santa Cruz CA
Yassin Mehmandoust - Santa Cruz CA
James M. Olivas - Scotts Valley CA

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

F26B 2108

US Classification:

34557, 34196, 34197, 34228, 34527, 134 61, 1341044, 134137

Abstract:

Liquid is removed from batches of substrates by apparatus and methods for drying substrates that have been wet in an elongated liquid bath. The substrates are moved relative to the bath and an elongated gas-filled volume at rates of movement selected according to the location of the batches of substrates in the bath or the volume. As an example, the substrates and the bath are separated at a controlled rate to form a thin layer of liquid on each substrate as each substrate enters the gas-filled volume. The gas-filled volume is defined by an elongated hot chamber and hot gas directed into the volume and across the substrates and out of the volume continuously transfers thermal energy to the substrates. The flow rate of the gas into the volume is related to introduction of the substrates into the bath to avoid disturbing the liquid in the bath. The thermal energy transferred to the substrates in the volume evaporates the thin layer from the substrates without decreasing the rate of separation of the substrates and the bath below the maximum rate of such separation at which a meniscus will form between the bath and the surface of one of the substrates during such separation.

US Patent:

44380704, Mar 20, 1984

Filed:

Dec 4, 1981

Appl. No.:

6/327379

Inventors:

Donald E. Stephens - Palo Alto CA
Thomas D. Sharples - Atherton CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01N 3108

US Classification:

422 70

Abstract:

An elongate straight column for use as a reactor in an analytical instrument. The column contains inert packed material which provides for the necessary flow path length for a fluid stream entering the reactor. Fittings are incorporated onto the ends of the column in such a manner that their width is no larger than the width of the column. The column configuration for a reactor allows more versatility in the type of temperature regulator mechanisms used to heat and cool the reactor.

US Patent:

42947995, Oct 13, 1981

Filed:

Apr 24, 1980

Appl. No.:

6/143212

Inventors:

Donald E. Stephens - Palo Alto CA
John T. Taylor - Santa Clara CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01N 3122
G01N 3108
G01J 346

US Classification:

422 62

Abstract:

A temperature regulating apparatus which increases optical sensitivity and resolution of a liquid in a reaction chamber by heating while providing rapid cooling to prevent vaporization of the liquid within the reaction chamber. The apparatus includes a heat exchanger containing the reaction chamber and an insulating chamber surrounding the heat exchanger. A coolant may be passed through the heat exchanger to prevent boiling should a change in liquid flow make such occurrence likely. The change in liquid flow is monitored by an analyzer monitor, and the temperature in the reaction chamber is changed accordingly.

US Patent:

45349410, Aug 13, 1985

Filed:

Dec 4, 1981

Appl. No.:

6/327372

Inventors:

Donald E. Stephens - Palo Alto CA
Robert J. Ehret - Los Altos CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01N 3108

US Classification:

422 70

Abstract:

A temperature control system used to precisely and accurately control the temperature of a fluid stream in an analytical system designed for investigation of the chemical constituents of the fluid stream. One example of use is in chromatography such as for the chromatographic column in an amino acid analyzer system. The temperature control system utilizes a set of thermoelectric modules to transfer heat between a thermoconductive block which holds the chromatographic column and an air exchange heat sink which obtains heat from or disposes heat into ambient air as required. The control system regulates the temperature at a very rapid rate in order to minimize the recycle time of the instrument.

US Patent:

43721508, Feb 8, 1983

Filed:

Jun 5, 1980

Appl. No.:

6/156718

Inventors:

Donald E. Stephens - Palo Alto CA
Robert J. Ehret - Los Altos CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01M 328

US Classification:

73 405R

Abstract:

A method and apparatus for monitoring flow rate through a conduit. A flow number indicative of the flow rate of a liquid through the conduit is compared with a preselected reference number. The actual liquid flow through the conduit provides a clocking signal which determines the time span during which a count signal, indicative of the intended flow rate into the conduit, is accumulated thereby providing the flow number.

US Patent:

45187002, May 21, 1985

Filed:

Dec 4, 1981

Appl. No.:

6/327378

Inventors:

Donald E. Stephens - Palo Alto CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01N 3108

US Classification:

436 52

Abstract:

A temperature control apparatus for a high temperature reactor in an analytical instrument of the type in which a development reagent is added to a flowing stream as part of the detection process. The temperature control apparatus utilizes solid state heat transfer means to transfer heat between a thermoconductive block to which is mounted the reactor and an air exchange heat sink which obtains heat from or disposes heat into ambient air as required. The control apparatus regulates the temperature of the reactor at a very rapid rate in the high temperature range of approximately 90. degree. C. to 150. degree. C. without the use of a separately contained heat exchange medium. The ability of the apparatus to cool the reactor rapidly eliminates the requirement to keep reactor contents at elevated pressures to prevent vaporization of the stream being analyzed.

US Patent:

49267027, May 22, 1990

Filed:

Sep 18, 1987

Appl. No.:

7/098573

Inventors:

Donald E. Stephens - Palo Alto CA
Manfred W. Unterbusch - Sunnyvale CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01N 114

US Classification:

7386483

Abstract:

A detector for detecting the presence of an electrically conductive sample solution in a sample injection metering valve by electrical sensing the leading edge of the sample solution, wherein the amount of sample solution in excess of the metered amount required to cause detection is minimized. A conductive probe is positioned on the valve body just downstream of the sample metering passage of the valve, the probe being electrically insulated from the valve body. The probe and valve body form electrodes which will detect the arrival of the leading edge of a conductive sample solution which completes a conductive circuit between the electrodes.

US Patent:

39414876, Mar 2, 1976

Filed:

Oct 18, 1974

Appl. No.:

5/516008

Inventors:

Robert J. Ehret - Los Altos CA
Donald E. Stephens - Palo Alto CA
Douglas H. Durland - Palo Alto CA
Thomas D. Sharples - Atherton CA

Assignee:

Beckman Instruments, Inc. - Fullerton CA

International Classification:

G01J 346
G01N 2128
G01N 110

US Classification:

356181

Abstract:

A light beam is passed through a cuvette, through which flows liquid to be analyzed optically for concentration of color reacted amino acids. The emergent beam is directed through a series of dichroic beam separators and pass band filters to produce three beams of substantially three different wavelengths. Photoelectric detectors produce electrical signals corresponding to each of the three wavelengths. Two of the signals are characteristic of the substance to be detected. The third is subtracted from the other two wavelength signals to produce a pair of output signals from which base line noise has been substantially eliminated.