Abstract: A microwave monolithic integrated circuit assembly includes a microwave monolithic integrated circuit having an MMIC circuit plane and having a first region of relatively high heat production and a second region of relatively low heat production. A heat-dissipating assembly is in thermal contact with the microwave monolithic integrated circuit. The heat-dissipating assembly has at least two pieces of pyrolytic graphite embedded within a casing. The pieces of pyrolytic graphite include a first piece of pyrolytic graphite underlying the first region and having a high-thermal-conductivity x-direction of the first piece lying within about 20 degrees of a perpendicular to the MMIC circuit plane, and a second piece of pyrolytic graphite underlying the second region and having a high-thermal-conductivity x-direction of the second piece lying within about 20 degrees of the MMIC circuit plane. The heat-dissipating assembly is preferably fabricated by hot isostatic pressing.

Abstract: A microwave monolithic integrated circuit assembly includes a microwave monolithic integrated circuit having an MMIC circuit plane and having a first region of relatively high heat production and a second region of relatively low heat production. A heat-dissipating assembly is in thermal contact with the microwave monolithic integrated circuit. The heat-dissipating assembly has at least two pieces of pyrolytic graphite embedded within a casing. The pieces of pyrolytic graphite include a first piece of pyrolytic graphite underlying the first region and having a high-thermal-conductivity x-direction of the first piece lying within about 20 degrees of a perpendicular to the MMIC circuit plane, and a second piece of pyrolytic graphite underlying the second region and having a high-thermal-conductivity x-direction of the second piece lying within about 20 degrees of the MMIC circuit plane. The heat-dissipating assembly is preferably fabricated by hot isostatic pressing.

Abstract: A phased array (20) and method for constructing the same are disclosed. The phased array (20) includes a superstructure (22) with cavities (40) therein. A cover plate (28) is mounted to the superstructure (22) and cooperates with the cavities (40) to form cavity style filters therebetween and to form a box-beam type superstructure. Ideally, the superstructure (22) is self supporting. Electronic modules (32) and amplifiers (33) are mounted to the superstructure (22). The method includes machining a block of material to form a webbed superstructure with cavities (40) therein. A cover plate (28) is mounted to the superstructure (22) over the cavities (40) to form cavity style filters. Amplifiers (32) and antenna elements (30) are then affixed to the superstructure (22) and cover plate (28). Ideally, the cover plate (28) is affixed to the superstructure (22) using an electrically conductive adhesive.

Abstract: A ceramic-polymer composite material such as part of a microelectronics package is formed of a ceramic mixture of aluminum nitride and boron nitride, and a low-loss polymeric material. The amount of aluminum nitride is preferably from about 50 to about 90 weight percent of the ceramic mixture, but the relative amounts of the two ceramics may be adjusted to achieve thermal expansion and thermal conductivity properties required for a particular application. A mixture of the ceramics and uncured thermosetting polymeric resin is formed, pressed into the shape of the microelectronics base and/or lid, and heated (either concurrently or subsequently) to compress the mixture and cure the polymer.

Abstract: An electronic structure is formed of alternating layers of a metal and a cured ceramic-polymer mixture. The ceramic-polymer mixture is prepared by mixing small ceramic particles into a flowable, curable polymer. The mixture is spread over a first metallic layer and, optionally, B-stage cured. Additional metallic layers and ceramic-polymer layers are added in alternating fashion. Metallic interconnects may be provided through overlying ceramic-polymer layers to a particular metallic layer. The resulting structure is heated to a moderate temperature to cure the polymer.

Abstract: A phased array (20) and method for constructing the same are disclosed. The phased array (20) includes a superstructure (22) with cavities (40) therein. A cover plate (28) is mounted to the superstructure (22) and cooperates with the cavities (40) to form cavity style filters therebetween and to form a box-beam type superstructure. Ideally, the superstructure (22) is self supporting. Electronic modules (32) and amplifiers (33) are mounted to the superstructure (22). The method includes machining a block of material to form a webbed superstructure with cavities (40) therein. A cover plate (28) is mounted to the superstructure (22) over the cavities (40) to form cavity style filters. Amplifiers (32) and antenna elements (30) are then affixed to the superstructure (22) and cover plate (28). Ideally, the cover plate (28) is affixed to the superstructure (22) using an electrically conductive adhesive.