Here is the abstract you requested from the IMAPS_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Improved Thermal Management in High Power Applications by Utilizing Novel “Filled Vias” Thin Film Substrate Technology|
|Keywords: Thin Film, Copper, Thermal Management|
|Airborne and space borne SAR instruments with active array antennas will become more and more important in near future. One of the key elements in this kind of antennas are the hundreds or thousands of T/R Modules which are connected to discrete radiators arranged in array configurations. These T/R-Modules, each requiring separate electrical connections and amplifier circuits, are the cost-driver of the overall system. For such modules, the use of advanced substrate technologies can improve the system properties and enhance the overall performance. Especially in applications dealing with high power amplifiers or laser diodes, the thermal management is a crucial topic. Whereas, conventional RF substrate technologies use only partly metallized vias for through-substrate interconnects, our new technology provides solid Cu filled vias. These, together with high thermal conductivity substrate materials, like e.g. AlN, improve the thermal properties of the whole assembly. Naturally, also the electrical resistance is reduced and power loss minimized. Also according to manufacturing issues, some drawbacks of only partly metallized through-holes can be avoided. Besides the substrate itself, the properties of mechanical and thermal mounting of devices to the substrate has to be considered for excellent overall performance. Since, at the moment, most RF devices are realized on GaAs material, which has a relatively poor thermal conductivity, the thermal coupling to the substrate is very important. Thus, e.g. void free soldering techniques for chip attachment have to be applied. Our paper will deal with the manufacturing issues of the advanced RF substrates with Cu filled via interconnects and the incorporation in RF applications. Additional focus will be laid on the thermal properties and behaviour of the patterned and assembled substrates.|
|Alexander Kaiser, Technologist
Reinhardt Microtech GmbH
Ulm, BW 89077,