Northrop Grumman Systems Corporation

Westinghouse Electric Corporation

Peter A Stenger

Carl D Wise

Andrew Walters

David Krafcsik

Brian T McMonagle

Joseph Paquin

Fred C Kuss

Tujuana Hinton

Kevin LaCour

Craig Heffner

Steven D Block

Robert Sisk

Steven S Handley

Marvin Cohn

Edward C Niehenke

Mark E Schneider

Thomas A Andersen

A monolithic microwave integrated circuit (MMIC) flip chip interconnect is formed by coating an active side of the chip with a dielectric coating, such as benzocyclobutene (BCB), that inhibits deposition of metal plating materials. A portion of the dielectric coating is removed to expose bond pads on the active side of the chip, stud bumps are bonded to the bond pads, and the active side is then plated with first and second consecutive metal plating materials, such as nickel and gold, respectively, that do not adhere to the dielectric coating. The chip is then oriented such that the plated stud bumps on the active side of the chip face bond pads on a substrate, and the stud bumps on the chip are bonded to the bond pads on the substrate.

Flip chip interconnect method and design for GaAs MMIC applications

An MMIC chip is disclosed that includes a planar substrate having a first surface and a second surface, a conductive layer having an opening on the first surface, a transmission line on the second surface, at least one conductor extending from the conductive layer to the second surface defining a waveguide around the opening, wherein the transmission line is connected to the at least one conductor such that a signal traveling along the transmission line is guided toward the opening in the first side by the at least one conductor.

Transmission line to waveguide interconnect and method of forming same including a heat spreader

In one aspect, an embodiment of the invention provides a transition from a planar substrate/chip circuit microwave transmission line to waveguide transmission media on the back of the substrate/chip. The transition enables planar waveguide fed MMW ESA architectures to be realized within the tight grid spacing required for emerging MMW ESAs.

Transmission line to waveguide transition having a widened transmission with a window at the widened end

A vertically integrated Ka-band active electronically scanned antenna including, among other things, a transitioning RF waveguide relocator panel located behind a radiator faceplate and an array of beam control tiles respectively coupled to one of a plurality of transceiver modules via an RF manifold. Each of the beam control tiles includes a respective plurality of high power transmit/receive (T/R) cells as well as dielectric waveguides, RF stripline and coaxial transmission line elements. The waveguide relocator panel is preferably fabricated by a diffusion bonded copper laminate stack up with dielectric filling. The beam control tiles are preferably fabricated by the use of multiple layers of low temperature co-fired ceramic (LTCC) material laminated together. The waveguide relocator panel and the beam control tiles are designed to route RF signals to and from a respective transceiver module of four transceiver modules and a quadrature array of antenna radiators matched to free space formed in the faceplate. Planar type metal spring gaskets are provided between the interfacing layers so as to provide and ensure interconnection between mutually facing waveguide ports and to prevent RF leakage from around the perimeter of the waveguide ports. Cooling of the various components is achieved by a pair of planar forced air heat sink members which are located on either side of the array of beam control tiles. DC power and control of the T/R cells is provided by a printed circuit wiring board assembly located adjacent to the array of beam controlled tiles with solderless DC connections being provided by an arrangement of 'fuzz button' electrical connector elements.

Low profile active electronically scanned antenna (AESA) for Ka-band radar systems

A subharmonic image rejection and image enhancement mixer for mixing millimeter wavelength signals using a low conversion loss technique is described. A local oscillator frequency from an external source is fed to a first subharmonic mixer and through a phase shifter to a second subharmonic mixer. The phase shifter delays the local oscillator signal by (90.degree./n), where n is the multiple of the subharmonic mixers and is greater than 1. The first and second subharmonic mixers mix the local oscillator frequency with an input signal, which includes a desired frequency and an image frequency, to produce an intermediate frequency having a desired component and an image component at a select phase. A 0.degree.-90.degree. hybrid separates and terminates the image component of the intermediate frequency. The input port that feeds the input signal to each subharmonic mixer is dimensioned so as to provide a virtual image short termination or an image short termination to a self-generated image signal from each subharmonic mixer, thereby decreasing the conversion loss of the frequency mixer.

Subharmonic image rejection and image enhancement mixer

Growing community of inventors

Woodbine, MD, United States of America

Peter A Stenger