Raytheon Company

National Technology & Engineering Solutions of Sandia, LLC

Shahed Reza

Eduardo M Chumbes

Michael F Parkes

Michael David Henry

William E Hoke

Thomas E Kazior

Christopher M Laighton

Susan C Trulli

David H Altman

Brian D Schultz

Albert G Baca

Gerhard Sollner

Jeffrey H Saunders

Erica Ann Douglas

Roberto W Alm

Kenneth A Wilson

Keith R Kessler

Abbas Torabi

Maher Salloum

Edward Swiderski

Brianna Alexandra Klein

There is provided a transistor apparatus of the kind in which a gate electrode includes one or more gate fingers that extend laterally across a device area. At least one gate finger is not rectilinear, but instead describes two or more meanders about an average path across the device area. The meanders can be tapered such that a taper amplitude is smallest in a central part of the gate finger and increases toward end portions of the gate finger.

Transistor with curvilinear gate configuration for improved thermal distribution

A multichannel transistor is provided. In the transistor, a plurality of gate fingers overlie a substrate and extend laterally across the substrate from a gate manifold. The gate manifold has a curved edge, and each of the gate fingers projects radially from the curved manifold edge.

Multichannel transistor with improved gate conformation

A high current density, low contact resistance contact for wide bandgap (WBG) or ultra-wide bandgap materials (UWBG) is disclosed. The contact is lithographically formed so that a total perimeter length of the contact structure is at least twice the length of the side of a contact pad closest to the gate in a high electron mobility transistor (HEMT). The contact structure may take the form of a plurality of columns having various cross-sectional shapes, or may take the form of a convoluted geometrical shape, such as a comb-like, serpentine, or spiral shape. The depth of the contact structure permits direct contact with the two-dimensional electron gas (2DEG) in the HEMT by the perimeter of the contact structure. The contact structure is formed of at least one metal layer, at least one doped material regrown layer, or at least one implanted region. The contact structure may be applied to other WBG and UWBG devices.

High current density, low contact resistance wide bandgap contacts

A microwave structure having an input section for receiving both a common mode signal and a CPW differential mode signal; an output section; and a CPW transmission line, having a center conductor disposed between a pair of coplanar ground plane conductors, connected between the input section and the output section. The conductors of the CPW transmission line are configured to provide the common mode signal a different attenuation in passing to the output section than the CPW transmission line provides to the differential mode signal passing between the input section and the output section.

Coplanar waveguide transmission line structure configured into non-linear paths to define inductors which inhibit unwanted signals and pass desired signals

A transmission line structure having a pair of separated coplanar waveguide transmissions line section. A coupling circuit is coupled between the pair of coplanar waveguide transmissions line sections, the coupling circuit suppresses common mode signals therein and passes, substantially unsuppressed, differential mode signal transmission between the pair of coplanar waveguide transmissions line sections.

Microwave coupling structure for suppressing common mode signals while passing differential mode signals between a pair of coplanar waveguide (CPW) transmission lines

A semiconductor structure having a Group III-N buffer layer and a Group III-N barrier layer in direct contact to form a junction between the Group III-V buffer layer the Group III-N barrier layer producing a two dimensional electron gas (2DEG) channel, the Group III-N barrier layer having a varying dopant concentration. The lower region of the Group III-N barrier layer closest to the junction is void of intentionally introduced dopant and a region above the lower region having intentionally introduced, predetermined dopant with a predetermined doping concentration above 1&#xd7;10atoms per cm.

Doped barrier layers in epitaxial group III nitrides

A heterojunction semiconductor field effect transistor HFET having a pair of layers of different semiconductor materials forming a quantum well within the structure to support the 2DEG. Source, drain and gate electrodes are disposed above the channel. The HFET has a predetermined transconductance. A transconductance control electrode varies an electric field within the structure under the channel to vary the shape of the quantum well and thereby the transconductance of the FET in accordance with a variable control signal fed to the transconductance control electrode.

Heterojunction field effect transistor (HFET) variable gain amplifier having variable transconductance

A monolithic microwave integrated circuit structure having: a semiconductor substrate structure having a plurality of active devices and a microwave transmission line having an input section, an output section and a interconnecting section electrically interconnecting the active devices on one surface of the substrate; a thermally conductive, electrically non-conductive heat sink; and a thermally conductive bonding layer for bonding the heat sink to the substrate, the thermally conductive bonding layer having an electrically conductive portion and an electrically non-conductive portion, the electrically conductive portion being disposed between the heat sink and an opposite surface of a portion of the substrate having the active devices and the electrically non-conductive portion being disposed on the opposite surface portion overlaying portion of the microwave transmission line section.

Patterned conductive epoxy heat-sink attachment in a monolithic microwave integrated circuit (MMIC)

A semiconductor structure having: a Group III-N channel layer, a Group III-N top-barrier polarization-generating layer forming a heterojunction with an upper surface of the channel layer; and a Group III-N back-barrier polarization-generating layer forming a heterojunction with a lower surface of the channel layer. The channel layer has disposed therein a predetermined n-type conductive dopant.

Double heterojunction group III-nitride structures

A monolithic microwave integrated circuit structure having a semiconductor substrate structure with a plurality of active devices and a microwave transmission line having an input section, an output section and a interconnecting section electrically interconnecting the active devices on one surface and a metal layer on an opposite surface overlaying the interconnection section and absent from overlaying at least one of the input section and the output section.

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Boxborough, MA, United States of America

Shahed Reza