Westinghouse Electric Corporation

Northrop Grumman Systems Corporation

Timothy T Braggins

Robert Miles Young

Carl Baldwin Freidhoff

Richard N Thomas

Thomas V Congedo

John R Gavaler

Joseph C Kotvas

A gas ionizer is provided for use in a solid state mass spectrograph for analyzing a sample of gas. The gas ionizer is located in a cavity provided in a semiconductor substrate which includes an inlet for introducing the gas to be analyzed. The gas ionizer ionizes the sample of gas drawn into the cavity through the inlet to generate an ionized sample gas. The gas ionizer generates energetic particles or photons which bombard the gas to be sampled to produce ionized gas. The energetic particles or photons can be generated by reverse-bias p-n junctions, radioactive isotopes, electron discharges, point emitters, and thermionic electron emitters. A layer of cesium chloride or cesium iodide having a low work function is formed on top of the reverse-bias p-n junction gas ionizer to increase current emitted per junction area and so that the gas ionizer can be exposed to atmospheric oxygen during storage and can operate in reduced atmosphere with no additional treatments. The cesium chloride layer and the cesium iodide layer do not readily electromigrate. A fabrication process of the mass spectrograph includes using plural masks to ensure proper exposure of resist on both flat and wall surfaces of the semiconductor surface having severe topography.

Micro-miniature ionizer for gas sensor applications and method of making

A method for forming a solid state mass spectrograph for analyzing a sample gas is provided in which a plurality of cavities are formed in a substrate, preferably, a semiconductor. Each of these cavities forms a chamber into which a different component of the mass spectrograph is provided. A plurality of orifices are formed between each of the cavities, forming an interconnecting passageway between each of the chambers. A dielectric layer is provided inside the cavities to serve as a separator between the substrate and electrodes to be later deposited in the cavity. An ionizer is provided in one of the cavities and an ion detector is provided in another of the cavities. The formed substrate is provided in a circuit board which contains interfacing and controlling electronics for the mass spectrograph. Preferably, the substrate is formed in two halves and the chambers are formed in a corresponding arrangement in each of the substrate halves. The substrate halves are then bonded together after the components are provided therein.

Method for manufacturing a miniaturized solid state mass spectrograph

A superconducting film is deposited in a closed, non-baked reactor (10) containing a sputtering gas comprising O.sub.2 with H.sub.2 O vapor addition to preferably provide a total H.sub.2 O vapor pressure of between 3.times.10.sup.-3 mbar to 266.times.10.sup.-3 mbar, where a copper oxide-based target material (15) is used and the deposition substrates (16) are maintained between 550.degree. C. and 800.degree. C.

Sputtering method for forming superconductive films using water vapor

A method and apparatus for removing heavy metal impurities such as gold, silver, nickel and copper from a crystalline substrate is described incorporating a damaged crystalline layer which may be formed by excessive doping to trap or getter heavy metal impurities to enhance the majority carrier lifetime of the detector material. The invention overcomes the problem of degraded responsivity in radiant energy crystalline detectors after high temperature processing, in excess of 900.degree. C., which permits surface contaminants such as gold, silver, nickel and copper to diffuse through the detector material raising the net donor density.

Growing community of inventors

Penn Hills, PA, United States of America

Timothy T Braggins