General Instrument Corporation

Cree Research Inc.

Muni M Mitchell

Willem G Einthoven

Mohammad Sedigh

John Adam Edmond

Douglas G Waltz

Robert L Fried

Richard Shyr

Lou Schilling

Roman Hamerski

Edward Shih

Sets of six steering diodes and an ungated Thyristor are simultaneously formed into surge protection circuit modules by mass production techniques. An extended lead frame is provided with three spaced parallel leads for each module. The leads are connected at one end by a bridge. The sets of components are arranged along the lead frame in a fixture. By heating, each lead is soldered between a pair of steering diodes and the steering diodes on each side of the lead frame are soldered to different conductive plates. A thyristor is soldered between the plates. The partially formed modules are removed as a unit from the fixture and may be encased simultaneously. The bridge is removed to separate the modules and the leads trimmed and bent as required.

Surge protection circuit module and method for assembling same

The rectifier sub-assembly, formed by high temperature brazing, is glass encapsulated. It has axially extending leads with enlarged head portions. The sub-assembly is prepared for surface mounting by first flattening the leads outwardly from the enlarged head portions. An electrically insulating, heat conductive epoxy body is molded around the capsule, the enlarged head portions and at least a portion of each of the flattened lead sections. The leads are trimmed and if required, bent into the appropriate shape. After forming, the leads are barrel plated to obtain the best solderable surface for the most reliable electrical connection.

Surface mountable rectifier and method for fabricating same

A rectifier is fabricated from a P-N junction having a P-type semiconductor layer and an adjacent N-type semiconductor layer. A mesa structure is formed in at least one of said layers. Impurities are deposited at the top of the mesa to form a high concentration region in the surface thereof. The impurities are diffused from the top surface of the mesa toward the P-N junction, whereby the mesa geometry causes the diffusion to take on a generally concave shape as it penetrates into the mesa. The distance between the perimeter of the high concentration region and the wafer substrate is therefore greater than the distance between the central portion of said region and the wafer substrate, providing improved breakdown voltage characteristics and a lower surface field. Breakdown voltage can be measured during device fabrication and precisely controlled by additional diffusions to drive the high concentration region to the required depth.

Method for fabricating a rectifying semiconductor junction having

The invention is a packaged diode suitable for operation at temperatures above 200.degree. C. and during temperature excursions between -65.degree. C. and at least 350.degree. C. The invention comprises a diode having respective p-n portions with a p-n junction therebetween, and formed of a semiconductor material that is stable and will exhibit satisfactory diode characteristics at such temperatures. Ohmic contacts are made to the opposite sides of the junction diode and to the respective p and n portions of the diode. An electrode adjacent each of the ohmic contacts is formed of an electrically conductive material that has a coefficient of thermal expansion similar to the coefficient of thermal expansion of the semiconductor material for providing structural support to the junction diode and electrical contact therewith. A lead contacts each of the electrodes opposite each electrode's contact with the diode. Each lead is formed of an electrically conductive material and is joined to the respective electrode by an alloy that likewise remains physically and electrically stable at temperatures greater than 200.degree. C. and during repetitive operating cycles over temperature excursions between about -65.degree. C. and 350.degree. C. A packaging material surrounds the junction diode and portions of the electrode to hermetically seal it.

Packaged diode for high temperature operation

Rectifying P-N junction having improved breakdown voltage

Method for fabricating a rectifying P-N junction having improved

A power, V-grooved MOSFET having V-grooves extending in two orthogonal dimensions, thereby forming a semi-continuous mesh grid configuration which maximizes the periphery of the MOSFET channels for a given area of silicon, thus providing higher output current and lower 'on resistance' for a given area than a conventional, interdigitated V-MOS power transistor having V-grooves running in only one dimension.

Growing community of inventors

Huntington, NY, United States of America

Muni M Mitchell