Mks Instruments, Inc.

Wenzel Instruments, Aps

Garry Holcomb

Youfan Gu

Ole Wenzel

Paul Dozoretz

James M Mueller

Stacy Wade

James Stafford

A method and apparatus integrates differential pressure measurements and absolute pressure measurements to provide a continuous absolute pressure profile over a wide range of pressures on a single integrated scale. The absolute pressure measurements and differential pressure measurements are obtained, and a correlation factor between the absolute pressure measurements and the differential pressure measurements is determined. The correlation factor is used to normalize the differential pressure measurements to virtual absolute pressure values on a common absolute pressure scale with the absolute pressure measurements. An absolute pressure profile over a wide pressure range includes the absolute pressure measurements in a portion of the range where the absolute pressure measurements are accurate, and it includes the virtual absolute pressure values in another portion of the range where the differential pressure measurements are accurate.

Integrated absolute and differential pressure transducer

A pirani absolute pressure sensor for sensing absolute pressure in a load lock in a range from 100 to 10torr and a differential pressure sensor for sensing a pressure difference between ambient atmospheric pressure and pressure in the load lock chamber are combined together in a module with a manifold and common circuit components to provide a pressure transducer that is capable of producing not only analog output for absolute pressure measurements, but also control signals at settable absolute and differential pressure values for opening interior and exterior doors of a load lock used to shuttle wafers and other devices into and out of a vacuum processing chamber. The transducer can also produce signals to control transition from slow to fast vacuum pumping of the load lock chamber at a settable threshold pressure.

Method of using a combination differential and absolute pressure transducer for controlling a load lock

A method and apparatus integrates differential pressure measurements and absolute pressure measurements to provide virtual absolute pressure measurements over a wide range of pressures on a single integrated scale.

Transducer apparatus and method combining both an absolute pressure sensor for sensing absolute pressure in the load lock chamber and a differential pressure sensor for sensing a pressure difference between ambient atmospheric pressure and pressure in a load lock chamber and provides control signals for opening an interior door from the load lock chamber into a vacuum processing chamber and for opening an exterior door between ambient atmosphere and the load lock chamber. The transducer can also produce signals to control transition from slow to fast vacuum pump-down of load lock chamber pressure at a predetermined pressure set point.

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Boulder, CO, United States of America

Garry Holcomb