Showing papers by "Fred Barlow published in 1997"

High Density Power Modules: A Packaging Strategy

Abstract: The current trend in commercial and industrial drives, such as electric vehicles and electronic motor drives, is toward the elimination of traditional mechanical or electromechanical systems in favor of power electronics systems (1kW and larger). Market pressures are forcing the design and packaging of power electronics to be compact in size, more reliable, thermally superior, and integrated with intelligence and control systems. As a result, new strategies in the topology design and materials selection are needed in order to fulfill these highly demanding requirements. Toward that end, the researchers have developed a low cost Power Packaging Strategy which extends the concept of Multichip Modules to high power electronic assemblies. This paper will discuss a novel power packaging design which allows for two high conductivity metal layers for power routing and up to ten layers of signal routing in a single compact module. Low power control and interface circuits have been integrated into the power module in bare die and packaged form using chip and wire as well as surface mount attachment. Proper thermal management is achieved through the use of an integrated Metal Matrix Composite heat spreader and substrate. In addition, a 3kW inverter has been fabricated using both the conventional approach and the new packaging concept. A thermal analysis and electrical characterization, as well as a comparison of these power module designs have been performed in this work and will be discussed in the paper.

Microelectronics and electronic packaging education and research at Virginia Tech

Abstract: Instruction and research at Virginia Tech, in the area of Microelectronics and Electronic Packaging, center around a core group of students and faculty in the Microelectronics Laboratory. This group offers courses in microelectronics with a strong emphasis on multichip module design and fabrication, interconnects, and electronic packaging, and include an introductory course in microelectronics as well as several graduate courses in electronic packaging, electronic devices, and microwave circuit design and fabrication. This paper outlines these instructional and research efforts as well as the capabilities of the Microelectronics laboratory. In addition, the courses structure and recent efforts to expand the microelectronics education to include integrated circuit fabrication, as well as advances in power electronic packaging will be discussed in this paper.

Miniaturization of power supplies with emphasis on integrated passive components

Abstract: This paper addresses miniaturization of power supplies with emphasis on thick film passive components integration. Three key issues need to be addressed; electrical simulation and characterization, thermal analysis, simulation and verification, and materials characterization; therefore, these issues are examined in this work. Thick film passive components (capacitors and resistors) have been evaluated for use in the miniaturization of power electronic circuits. Also, guidelines for the design implementation and steps necessary to integrate these passive components on prefired Alumina (Al 2 O 3 ) and Aluminum Nitride (AIN) ceramic surfaces have been generated. Thick film capacitors on the order of 120pF/mm 2 with breakdown voltage ratings of 250V have been fabricated on prefired Aluminum Nitride, as well as stable resistors ranging in value from a few ohms to several Megaohms have been also evaluated in this work. The use of Aluminum Nitride, as a high performance ceramic substrate, and the resulting issues concerning compatible thick film pastes, have also been investigated and the thermal properties of these components have been studied. Since a sizable amount of heat is generated by power electronic circuits, the integrated components are analyzed with respect to tolerance and degeneration over a wide temperature range.