Pacific Bell

General Electric Company

At&t Bell Laboratories

Bell Telephone Laboratories

James E Kohl

Robert S Scott

Michael S Adler

William P Kornrumpf

John D Harnden, Jr

Adrian R Hartman

Eric J Wildi

Herbert S Cole

Yiu-Huen Wong

Donald L Watrous

William F MacPherson

Harry T Weston

Terence J Riley

Deva N Pattanaya

William L Buchanan, Jr

A piezoelectric relay requiring less piezoelectric material than conventional piezoelectric relays is disclosed. The relay differs from conventional relays in that the contacts are touching with essentially no force applied between the contacts when no power is applied to the relay.

Piezo-electric relay

An area saving dielectrically isolated semiconductor structure is disclosed which allows for the merger of a plurality of active devices, which share a common terminal, in a single dielectrically isolated (DI) island, or tub. In particular, an isolation groove is formed in the bottom of the DI tub and extends upwards toward the top surface of the semiconductor structure. The common diffusion region associated with the common terminal is located in the DI tub directly over the isolation groove. The isolation groove and common diffusion region thus separate the single DI tub into isolated sections, where a separate active device can be formed in each section. Isolation is achieved through the interaction of the groove with the common diffusion region to 'pinch off' the conductive channel between devices in the DI tub. In a preferred embodiment, an inverted V-shaped isolation groove is utilized so as not to complicate the fabrication process. In order to merge a large plurality of devices in a single DI tub, a plurality of isolation grooves may be utilized to divide the single DI tub into a number of separate isolated sections.

Inverted groove isolation technique for merging dielectrically isolated

A method of forming a multilayer metallization pattern using siloxane polyimide dielectric layers comprises forming the first siloxane polyimide layer, laser etching holes in the first layer, plasma etching the first layer to be sure the holes are clean, then cleaning the surface of the first layer in an etchant for silicon oxide, after which the metallization layer is formed and patterned and a second siloxane polyimide layer is formed thereover with good adhesion.

Method of processing siloxane-polyimides for electronic packaging

An integrated circuit in which a large potential can be maintained between the source of the device and the substrate on which this device and other devices are fabricated is described. The circuit employs a minority carrier sink region to remove minority carriers from the gate region of a MOS depletion device. The sink region is shielded from the substrate by a buried layer which prevents punch-through between the sink region and the substrate.

High-voltage pull-up device

A method and apparatus for detecting and locating defective crosspoint switches in a path consisting of a plurality of conducting segments connected by switch points is disclosed. The method and apparatus utilize the change in capacitance of the path which occurs when the switches are operated in a predetermined order.

System for detecting and locating defective crosspoint switches

A circuit for driving an output between two voltage states in response to a control signal is disclosed. The circuit requires a very small amount of power in its quiescent state. The circuit comprises a first switch including first and second control terminals that provides a conductive path from a first source of potential to an output terminal when the potential difference between the control terminals is less than a first predetermined threshold value and for electrically isolating the first source of potential from the output terminal when the potential difference between the control terminals is greater than the first predetermined threshold value, and a second switch that provides a conductive path between a second source of potential and the output terminal when the first switch electrically isolates the first source of potential from the output terminal. The second switch electrically isolates the output terminal from the second source of potential when the first switch provides a conductive path from the first source of potential to the output terminal. The circuit also includes a control circuit for causing the potential difference between the first and second control terminals of the first switch to be greater than the first threshold value in response to a predetermined signal on the circuit input terminal and causes the potential difference between the first and second control terminals of the first switch to be less than the first threshold value when the predetermined signal is not present on the circuit input terminal.

Low power high voltage driver circuit

A switch is provided wherein a piezoelectric bimorph element is used to provide many separately controllable, closely spaced switchable contacts. The element includes at least two oppositely extending fingers connected by a common spine. The element spine is mounted to a case with the fingers spaced from an inner case surface. Electronic circuit means are mounted on the element spine for applying a separate electrical potential to each of the element fingers. A separate movable electrical contact is disposed on each of the element fingers spaced from the spine and insulated from the means for applying the separate electrical potentials to the fingers. A separate stationary contact is provided on an inner case surface opposite each of the movable contacts. In operations, a separate electrical potential is applied to each of the element fingers for selectively causing each finger to deflect and force its movable contact into electrical connection with the opposing stationary contact.

Piezoelectric switch

A switch is provided wherein a piezoelectric bimorph element is used to provide many separately controllable, closely spaced switchable contacts. The element includes at least two oppositely extending fingers connected by a common spine. The element spine is mounted to a case with the fingers spaced from an inner case surface. Electronic circuit means are mounted on the element spine for applying a separate electrical potential to each of the element fingers. A separate movable electrical contact is disposed on each of the element fingers spaced from the spine and insulated from the means for applying the separate electrical potentials to the fingers. A separate stationary contact is provided on an inner case surface opposite each of the movable contacts. In operation, a separate electrical potential is applied to each of the element fingers for selectively causing each finger to deflect and force its movable contact into electrical connection with the opposing stationary contact.

High voltage semiconductor devices include a drift layer region underlying a field gate electrode, the drift layer region having a selected charge density of lesser magnitude than the charge density of the remainder of the drift layer. This tailoring of the charge density of the drift layer region lowers the pinch-off voltage of a MOSFET inherent in the drift layer region. This lower pinch-off voltage decreases the potential of a device buried-layer when the device is in a reverse blocking mode of operation.

High voltage semiconductor devices electrically isolated from an

The present invention relates to an improved Schottky barrier device wherein the leakage current present in the reverse bias mode attributed to the presence of an electric field at the Schottky barrier (18) is significantly reduced by the inclusion of one or more field shields (22), P.sup.+ -type diffusions located under the metal anode (16) of the Schottky barrier device at the Schottky barrier (18). The P.sup.+ -type field shields, which are disposed in a pattern on the surface of the Schottky barrier, reduce the surface electric field present, thereby significantly reducing the leakage current related thereto.

Field shields for Schottky barrier devices

Control circuitry used with the combination of a control switch (typically a gated diode switch GDS) which is coupled to a control (gate) terminal of a like load switch which consists essentially of first and second p-n-p transistors. The collector of the first p-n-p transistor is coupled to an anode of the control switch. The emitter of the first p-n-p transistor is coupled to the base of the second p-n-p transistor and to a control circuitry input terminal. The collector of the second p-n-p transistor is coupled to a gate terminal of the control switch. The control circuitry limits undesirable current flow into the load switch and has fewer components than commonly used control circuitry which performs a like function.

Growing community of inventors

Schenectady, NY, United States of America

James E Kohl