Reliable Integration of Double-Sided Cooled Stacked Power Switches based on 70 micrometer Thin IGBTs and Diodes

A stacked assembly concept of substrate-chip-bump-chip-substrate has been developed for a bi-directional power switch based on the latest generation Infineon Technologies(R) 70 micrometer thin IGBTs and diodes, rated at 200A-600 V. Using solder joints as joining method, this paper mainly reports the thermo-mechanical simulation to optimize the design of such a stacked assembly with consideration of substrates and bump shapes for maximizing the thermal performance of the chips and minimizing stress and creep strain development in the solder joints.The simulated results reveal that the thickest AlN-based substrate offers the best thermal performance, while the thinnest Si3N4-based substrate leads to the lowest creep strain accumulation in the critical solder joints. The effect of the bump shapes on the thermal performance is negligible, while hollow cylinder bumps can reduce the creep strain accumulation in the critical solder joints when compared to the solid cylinder bumps. In addition, a preliminary experiment demonstrates that the stacked integration can achieve the electrical function of the bi-directional power switch.

[1]  Alberto Castellazzi,et al.  Virtual reliability assessment of integrated power switches based on multi-domain simulation approach , 2007, Microelectron. Reliab..

[2]  Alberto Castellazzi,et al.  3D Integration of a three-phase bi-directional power switch , 2011, Proceedings of the 2011 14th European Conference on Power Electronics and Applications.

[3]  E. Woirgard,et al.  Thermomechanical modelling and reliability study of an IGBT module for an aeronautical application , 2008, EuroSimE 2008 - International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Micro-Systems.

[4]  Michel Mermet-Guyennet.  New structure of power integrated module , 2006 .

[5]  William W. Sheng,et al.  Power Electronic Modules: Design and Manufacture , 2004 .

[6]  Hsueh-Rong Chang,et al.  300A 650V 70 um thin IGBTs with double-sided cooling , 2011, 2011 IEEE 23rd International Symposium on Power Semiconductor Devices and ICs.

[7]  G. Amaratunga,et al.  Compact Double-Side Liquid-Impingement-Cooled Integrated Power Electronic Module , 2007, Proceedings of the 19th International Symposium on Power Semiconductor Devices and IC's.

[8]  Alberto Castellazzi,et al.  Application driven integrated design of a half-bridge power switch , 2011, 2011 IEEE 23rd International Symposium on Power Semiconductor Devices and ICs.

[9]  A. Bouzourene,et al.  Lifetime and Reliability Assessment of AlN Substrates Used in Harsh Aeronautic Environments Power Switch Modules , 2010 .

[10]  A. Syed.  Accumulated creep strain and energy density based thermal fatigue life prediction models for SnAgCu solder joints , 2004, 2004 Proceedings. 54th Electronic Components and Technology Conference (IEEE Cat. No.04CH37546).

[11]  Guo-Quan Lu,et al.  Fracture mechanics analysis of the effect of substrate flexibility on solder joint reliability , 2005 .