T1 - Thermal mangement and reliability - Design, technology, verification

Dr. Bernhard Wunderle, Fraunhofer IZM Berlin

Dr. Bruno Michel, IBM Zürich

Dr. Hermann Oppermann, Fraunhofer IZM Berlin

Klaus Busch, Siemens AG Amberg

Prof. Dr. Ralph Schacht, Fraunhofer IZM Berlin & FH Lausitz

Dr. Eckart Hoene, Fraunhofer IZM Berlin

Dr. Bernhard Wunderle, Fraunhofer IZM Berlin

Continuously increasing power and power density of microelectronic systems have become one of the most important design concerns as they pose new challenges to heat spreading and overall heat removal. This necessitates the development of new thermal management strategies and technologies.

Today, competitive cooling solutions have to provide at the same time maximum performance, reliability and optimised cost. Further, they have to be integrated in the technology platform used for the respective field of application. This requires expertise in the fields of processes and materials. To meet the high standards given by industry for reliable system design and technology development, combined numerical and experimental techniques have become indispensable tools to that end, last but not least in view of time and cost considerations.

Special attention is attached to the field of reliability, as thermo-mechanical stresses and strains can be fatal for thermal design as well as EMC problems can lead to functional failure of the system. So this tutorial aims to give an overview over the most important cooling concepts with respect to design for reliability.

• Communicate status and advancements on the field of thermal management solutions
  • Natural convection, enforced air and liquid cooling
  • Heat conduction and 3D
• Present a system approach to cooling concepts design consisting of
  • Material selection & characterisation
  • Technology (FC, COB, DBC, Soldering, Encapsulation)
  • Simulation and design
  • Experimental verification
• Exemplify advanced thermal technology for
  • Micro-processors
  • Power-electronics
  • Power-LED
• Supply analytical and predictive methods for
  • Thermal performance
  • Thermo-mechanically reliable system design
  • Electro-magnetic compatibility

This course will benefit those who are interested in design and technology development for cooling systems with respect to performance, cost and reliability.

Although examples are given from specific fields (micro-processors, power-electronics, power-LED), the tutorial provides insight into a more general methodology presenting advanced technological, experimental and numerical techniques.

• Advanced Thermal Technology for µP Cooling
• Power Packaging Technologies
• Computational Fluid Dynamics Simulation
• Experimental Verification Techniques for Thermal Management
• Power Electronics and Electro-Magnetic Compatibility
• Reliability of Cooling Concepts

Bruno Michel received a Ph.D. degree in bio­chemistry/biophysics from the University of Zurich, Switzerland in 1988 and subsequently joined the IBM Zurich Research Laboratory to work on scanning probe microscopy and its applications to molecules and thin organic films. He started the Advanced Thermal Packaging group in Zurich in 2003. Main current research topics are microtechnology / microfluidics for efficient chip and datacenter thermal management, hybrid liquid / air coolers, 3D packaging, and thermophysics to understand heat transfer in nanomaterials and structures.

Hermann Oppermann studied Materials Science & Technology and received the Doctor degree in Materials Science. At Fraunhofer IZM he leads the group "Optoelectronics & RF System Integration". There he worked on power applications using approaches of fluxless die bonding soldering, thermocompression bonding and power enhanced flip chip solutions.

Klaus Busch is currently holding the position of an RD Manager in the Hardware Design Center of SIEMENS Automation Systems.He has experience in the development of mechanical switchgears and various electronic devices in industrial environment and in the field of FEM-simulation.

Ralph Schacht studied telecommunications and electro techniques in Berlin/Germany and got his Ph.D. in 2002 in electronic engineering at TU-Berlin/Germany.Since 2006 he is a professor at Fachhochschule Lausitz in Senftenberg/Germany for electronic circuit engineering. At Fraunhofer IZM, which he joined in 2001, he leads the Thermo-Electric Analysis Lab, specialising in thermal interface and system characterisation.  

Bernhard Wunderle received his diploma in theoretical physics from the University of Tübingen. From 1999 on he was with Robert Bosch Ltd, where he was concerned with reliability for electronic packages in automotive applications. After his Ph.D. in 2003 he joined Fraunhofer and currently leads a group in the field of material characterisation and reliability in experiment and simulation. He is responsible for the IZM thermal management program.

Eckart Hoene graduated as Diplom Ingenieur in electrical engineering at the Technical University Berlin, Germany in 1997. Since then he has been working with the Fraunhofer Institut for Reliability and Microintegration in Berlin as scientific assistant with the topic EMC in Power Electronics. He got his PhD degree in 2001 on the Topic “Prediction of EMI generated by electrical drive systems". Currently he is the leader of the IZM Power Electronics group.