In order to determine appropriate cooling solutions for 3D chip stacks in various cases, it is important to have a better understanding of the total thermal resistance of a 3D chip stack. For this purpose, precise thermal resistance measurements and modeling of each component of a 3D chip stack are important. The thermal resistance of interconnection is considered to be one of the thermal resis...

Deeply understanding HBT thermal characteristics and safe operating area (SOA) is critical to the improvement of the ruggedness and reliability of power amplifiers. In this work, we investigate the device size effect of SOA and thermal resistance by means of experimental measurement, analytical modeling and 3dimensional simulation. For HBTs with a factor of ten variations in emitter area, the S...

master moulds are used to cast copper anode moulds. these iron moulds are made of grey or nodular cast irons. according to desirable properties of ductile irons, it was expected that ductile cast iron moulds could have performed their nominal life. but in service, these moulds have not performed their nominal life and they have experienced premature failures due to warping and cracking. also gr...

Thermal diffusion measurements on polymethylmethacrylate-coated Si substrates using heated atomic force microscopy tips were performed to determine the contact resistance between an organic thin film and Si. The measurement methodology presented demonstrates how the thermal contrast signal obtained during a force-displacement ramp is used to quantify the resistance to heat transfer through an i...

Model Timo Veijola, Mikael Andersson*, and Antti Kallio Helsinki University of Technology, Faculty of Electrical Engineering, Circuit Theory Laboratory, Otakaari 5A, FIN-02150 Espoo, Finland. phone:+358-0-4512293, fax:+358-0-460224, e-mail:[email protected] *Nokia Research Center. P.O. Box 45, FIN-00211 Helsinki, Finland. Abstract| A simple method for transistor DC parameter extraction is prese...