Agilent Technologies, Inc.

Hewlett-packard Company

Motorola Corporation

John F Casey

Lewis R Dove

Marvin Glenn Wong

Rosemary O Johnson

Ling Liu

James R Drehle

R Frederick Rau, Jr

Julius K Botka

Anthony R Blume

Ron Jay Barnett

Philip J Yearsley

Ronald W Schroeder

Robert L Vyne

Paul Thomas Carson

Lewis R Dov

J Mark Foster

Wesley C Whiteley

Disclosed are methods for making microwave circuits using thickfilm components. In an embodiment, the method includes depositing a dielectric over a ground plane, and then forming a conductor on the dielectric. The conductor is formed by depositing a conductive thickfilm on the dielectric and then 'subsintering' the conductive thickfilm. In one embodiment, before the subsintering, the conductive thickfilm is patterned to define at least one conductor. In another embodiment, after the subsintering, the conductive thickfilm is patterned to define at least one conductor. After subsintering, the conductive thickfilm is etched to expose the conductor(s), and the conductor(s) are then fired at a full sintering temperature.

Methods for making microwave circuits

In a method for making a microwave circuit, a first dielectric is deposited over a ground plane, and then a conductor is formed on the first dielectric. A second dielectric is then deposited over the conductor and first dielectric, thereby encapsulating the conductor between the first and second dielectrics. In one embodiment, a ground shield layer is formed over the first and second dielectrics by 1) precoating the first and second dielectrics with a metallo-organic layer, and then 2) depositing a thickfilm ground shield layer over the precoat layer. Alternately, a ground shield layer is formed over the first and second dielectrics by 1) placing a polymer screen over the first and second dielectrics, and applying pressure to the polymer screen until it at least partially conforms to a contour of the dielectrics, and then 2) printing a thickfilm ground shield layer through the polymer screen.

Methods for making microwave circuits including a ground plane

Disclosed herein is a channel plate for a fluid-based switch. The channel plate is produced by 1) depositing a photoimagable dielectric layer onto a substrate, 2) photoimaging at least one channel plate feature on the dielectric layer, and 3) developing the dielectric layer to form the at least one channel plate feature in the dielectric layer, thereby forming the channel plate. A method for making a switch with a photoimaged channel plate is also disclosed.

Photoimaged channel plate for a switch, and method for making a switch using same

Disclosed is a method for forming a conductor on a dielectric. The method commences with the deposition of a conductive thickfilm on the dielectric, followed by a 'subsintering' of the conductive thickfilm. Either before or after the subsintering, the conductive thickfilm is patterned to define at least one conductor. After subsintering, the conductive thickfilm is etched to expose the conductor(s), and the conductor(s) are then fired. A brief chemical etch may be used after the final firing step if improved wire-bondability is required.

Methods for forming a conductor on a dielectric

Disclosed herein is a channel plate for a fluid-based switch. The channel plate is produced by 1) depositing a photoimagable dielectric layer onto a substrate, 2) photoimaging at least one channel plate feature on the dielectric layer, and 3) developing the dielectric layer to form the at least one channel plate feature in the dielectric layer, thereby forming the channel plate. Switches using photoimaged channel plates, and a method for making a switch with a photoimaged channel plate, are also disclosed.

Photoimaged channel plate for a switch

In one embodiment, a plurality of thickfilm dielectric layers are printed on a substrate, with each successive layer being printed over a previous layer, and with each layer having sloped walls. After printing a first subset of the plurality of thickfilm dielectric layers, a first conductive thickfilm is printed over at least the walls of the first subset of dielectric layers. Then, after printing a second subset of the plurality of thickfilm dielectric layers, a second conductive thickfilm is printed over the second subset of dielectric layers (with the first and second conductive thickfilms being electrically coupled).

Methods and apparatus for printing conductive thickfilms over thickfilm dielectrics

Disclosed are methods for making microwave circuits using thickfilm components, the thickfilm components including: a first, multi-layer thickfilm dielectric deposited on a ground plane; a thickfilm conductor deposited on the first thickfilm dielectric; a second, multi-layer thickfilm dielectric deposited on the first dielectric and conductor to encapsulate the conductor; a thickfilm ground shield layer deposited over the first and second dielectrics; and thickfilm resistors deposited in close proximity to the first and second dielectrics.

Disclosed herein is a switch having a photoimaged channel plate and a switching fluid. The photoimaged channel plate defines at least a portion of a number of cavities, a first cavity of which is defined by a first channel formed in the photoimaged channel plate. The switching fluid is held within one or more of the cavities, and is movable between at least first and second switch states in response to forces that are applied to the switching fluid.

Method and apparatus for interfacing a circuit, such as a microcircuit, with an IC. The circuit is formed on a thick film dielectric structure supported by a substrate having a cut out to receive the IC. A ground plane is formed on the substrate. The thick film dielectric structure abuts the cut out with an area having at least two projections forming at least one recess, the edge of the recess having a conductive layer in electrical communication with the ground plane. A conductive pad on top of the dielectric structure is in electrical communication with the conductive layer in the recess. A ground connection on the IC is connected to the conductive pad thereby grounding the IC.

Apparatus and method to form ground connections

Liquid metal micro-switches. Liquid metal micro-switches and techniques for fabricating them in integrally shielded microcircuits are disclosed. The liquid metal micro-switches can be integrated directly into the construction of shielded thick film microwave modules. This integration is useful in applications requiring high frequency switching with high levels of electrical isolation.

Electrically isolated liquid metal micro-switches for integrally shielded microcircuits

An efficient way to fabricate the channels and cavities in a LIMMS device is to form them as matching upper and lower portions each created as a patterned layer of thick film dielectric material deposited on a respective upper or lower substrate. The two portions are adhered together by a patterned layer of adhesive, and hermetically sealed around an outer perimeter. The heater resistors are mounted atop the lower layer, thus suspending them away from that substrate and exposing more of their surface area. Vias can be used to route the conductors for the heaters and the switched signal contacts through the lower substrate to cooperate with surface mount techniques using solder balls on an array of contact pads. These vias can be made hermetic by their placement within the patterned layers of dielectric material and by covering their exposed ends with pads of hermetic metal. Suitable thick film dielectric materials that may be deposited as a paste and subsequently cured include the KQ 150 and KQ 115 thick film dielectrics from Heracus and the 4141A/D thick film compositions from DuPont.

Liquid metal micro switches using as channels and heater cavities matching patterned thick film dielectric layers on opposing thin ceramic plates

Quasi-coaxial transmission lines to be &ldquo;crossed&rdquo; (over) are fabricated on a substrate. There are two cases: a true ground plane of metal will cover the substrate, or, each quasi-coaxial transmission line will have its own separate meandering bottom-half ground shield. In either case, when the crossed quasi-coaxial transmission lines are complete they will have top-half ground shields connected to metal against the substrate that is ground. If there is no ground plane the &ldquo;crossing&rdquo; quasi-coaxial transmission line that is to cross over must now have its bottom-half ground shield applied. It can overlay any top-half ground shield for any crossed quasi-coaxial transmission line that is in its path. If there is a ground plane, then that step is not necessary. Now a bottom-half layer of KQ dielectric material is applied along the path of the crossing quasi-coaxial transmission line. To this layer of KQ dielectric material is applied a layer of metal that becomes the center conductor. The crossing quasi-coaxial transmission line is finished by printing a top-half layer of KQ dielectric, covered by a layer of metal that is the top-half of ground shield. The edges of this top-half ground shield touch either the ground plane or the outer portion of the bottom-half ground shield.

Cross-over for quasi-coaxial transmission lines fabricated on a substrate

A preferred method includes providing a substrate and depositing a capacitor material upon the substrate. A portion of the capacitor material is then removed to form an interdigitated capacitor structure that incorporates a first contact and a second contact. Thereafter, a dielectric material is applied upon the interdigitated capacitor structure so that the structure is at least partially encapsulated by the substrate and the dielectric material. Capacitor structures also are provided.

Interdigitated capacitor with dielectric overlay

A hybrid circuit having a quasi-coaxial fully shielded conductor, and incorporating a ground plane on the component side of a substrate, can bypass and/or filter a signal using integrated thick film components and without through holes or vias. A thin pad of suitable dielectric material may be printed onto the ground plane and then have a layer of metal deposited on its top surface, forming a bypass capacitor. The bypass capacitor can be located very near where it is needed, and only a very short conductor is required to connect the metallic top of the bypass capacitor to the location to be bypassed. The short connecting conductor does not go from one side of the substrate to the other, and the thickness and low dielectric constant of the substrate do not compromise the value of the bypass capacitor. Thick film resistors can be included to form filters, and surface mount resistors and capacitors can be used also.

Growing community of inventors

Colorado Springs, CO, United States of America

John F Casey