Westinghouse Electric Corporation

Electric Power Research Institute Incorporated

Maurice H Hanes

Earl S Schlegel

Lewis R Lowry

Harvey C Nathanson

Michael W Cresswell

Karl F Schoch, Jr

John Bartko

Rowland C Clarke

Michael C Driver

Francis H Ruddy

Thomas J Smith, Jr

Richard J Fiedor

Lewis R Lowry, Jr

A silicon-based monolithic microwave integrated circuit architecture is described. This architecture, called MICROX.TM., is a combination of silicon material growth and wafer processing technologies. A wafer is fabricated using a substrate of high resistivity silicon material. An insulating layer is formed in the wafer below the surface area of active silicon, preferably using the SIMOX process. A monolithic circuit is fabricated on the wafer. A ground plane electrode is formed on the back of the wafer. Direct current and rf capacitive losses under microstrip interconnections and transistor source and drain electrodes are thereby minimized. Reduction in the resistivity of the substrate material as a result of CMOS processing can be minimized by maintaining a shielding layer over the bottom surface of the wafer. Microstrip and airbridge connectors, salicide processing and nitride side wall spacing can be used to further enhance device performance. The resulting architecture is an alternative to gallium arsenide integrated circuits for microwave applications.

Monolithic microwave integrated circuit on high resistivity silicon

Processes for producing stable, radiation hard, highly conductive polymers by a combination of chemical doping and ion irradiation and microelectronics are described. The highly conductive polymers formed by these processes may contain regions of different kinds of conductivity on the same polymer. Resist coatings and masks are used in conjunction with chemical doping and ion irradiation to create specific predetermined n and p conductivity patterns and insulation areas on polymeric films of selected thicknesses for electronic circuitry applications. The resulting circuitry, besides having a conductivity approaching that of metal, is extremely light in weight, flexible, and conductively stable. Several different configurations of microelectronic junction devices fabricated from single type or multiple type conductivity polymer films used either alone or with a polymer of opposite conductivity and a suitable metal or metals are disclosed.

Production of highly conductive polymers for electronic circuits

A bonded structure is described consisting of a semiconductor wafer, preferably gallium arsenide, soldered to a substrate material. A method for forming the structure is also described. The structure provides mechanical support and thermal conductivity for the wafer, as well as a multitude of connections through the substrate material at predetermined locations on the wafer. The substrate material and the soldering process are selected to minimize the resulting stresses in the wafer. A pattern of pads consisting of a refractory metal covered by a solder material is formed on the substrate to maintain space for excess solder in order to avoid the shorting of the individual connections on the wafer, and to control the size and location of voids in the solder upon solidification.

Semiconductor wafer with circuits bonded to a substrate

A four-layer semiconductor thyristor including a planar recombination region extending on both sides of a planar cathode-emitter junction.

Thyristor with continuous recombination center shunt across planar

A photo-transistor includes a multi-apertured collector electrode disposed on a semiconductor collector layer. A laser diode and a light pipe are provided for each aperture such that the light from the laser is transmitted to its associated aperture via the light pipe. Means are included for sequentially pulsing each laser so as to cause a high-frequency intermittent current in the photo-transistor piece of molybdenum 88 which provides improved current flow and heat sinking for the transistor 10.

High-frequency phototransistor operated with multiple light sources

An hermetically sealed package for a light-triggered thyristor. The thyristor is mounted within the cavity of an insulating body. Cathode and anode pole pieces are mounted on opposite sides of and electrically coupled with the thyristor. Annular flanges are provided to form hermetical seals between the body and pole pieces. A light pipe is mounted in a radially extending slot formed through a face of one pole piece. An inner end of the light pipe is optically coupled with a light-sensitive region of the thyristor. The outer end of the light pipe is mounted within a metal sleeve which radially projects through an opening formed in a side of the body. An hermetical seal is formed between the light pipe and inner end of the sleeve by means of a glass frit in one embodiment, or by means of solder bonded between the sleeve and a metallized region formed about the light pipe in another embodiment. Another hermetical seal is formed by solder which bonds between the metal sleeve and a metallized region formed in the body about the opening. A connector fitting is mounted on an outer end of the sleeve for seating the end of a fiber optic cable which extends from a triggering light source.

Package for light-triggered thyristor

A planar high power Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) including a substrate with an epitaxial layer on a surface thereof. A gate electrode including a strip of metal extending across a surface of the epitaxial layer and having a plurality of fingers extending therefrom along its length. The gate electrode being electrically insulated from the epitaxial layer by a layer of oxide. A source electrode in the surface of the epitaxial layer including fingers extending therefrom and interdigitating with the fingers of the gate electrode. There are p and n diffusion regions formed in the epitaxial layer except in an area under each of the gate fingers, which area remains undiffused. A drain electrode is connected to the surface of the substrate opposed to the surface upon which the epitaxial layer is deposited. During operation of the MOSFET as the blocking voltage across the transistor increases and the transistor is in the OFF state, the horizontal components of fields from the adjacent and closely spaced p-regions cancel each other so that voltage breakdown due to junction curvature is avoided.

Power metal-oxide-semiconductor-field-effect-transistor

A system for switching a high energy, short duration pulse from a high energy source to an impedance matched series load. A light activated semiconductor device having a rectifying junction is serially connected between the source and the load, and another light activated semiconductor device is connected in parallel across the load. A fast rise time laser light source sequentially activates the series connected device to initiate the energy pulse, and then actuates the device paralleled across the load to short circuit the load and terminate the energy pulse.

High energy, short duration pulse system

An hermetically sealed package for a light-triggered thyristor. The thyristor is mounted within the cavity of an insulating body. Cathode and anode pole pieces are mounted on opposite sides of and electrically coupled with the thyristor. Annular flanges are provided to form hermetical seals between the body and pole pieces. A light pipe is mounted in a radially extending slot formed through a face of one pole piece. An inner end of the light pipe is optically coupled with a light-sensitive region of the thyristor. The outer end of the light pipe is mounted within a metal sleeve which radially projects through an opening formed in a side of the body. A glass frit is bonded between the light pipe and inner end of the sleeve to form an hermetical seal. Another hermetical seal is formed by solder which bonds between the metal sleeve and a metalized region formed in the body about the opening. A connector fitting is mounted on an outer end of the sleeve for seating the end of a fiber optic cable which extends from a triggering light source.

Growing community of inventors

Murrysville, PA, United States of America

Maurice H Hanes