Research Repository

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Comparison of thermal and reliability performance between a SiC MOSFET module with embedded decoupling capacitors and commercial Si IGBT power modules (2018)
Conference Proceeding
Yang, L., Agyakwa, P., Corfield, M., Johnson, M., Harris, A., Packwood, M., & Paciura, K. (2018). Comparison of thermal and reliability performance between a SiC MOSFET module with embedded decoupling capacitors and commercial Si IGBT power modules

This paper characterizes thermal and reliability performance of a SiC MOSFET power module with embedded decoupling capacitors and without anti-parallel diodes. Active and passive temperature cycling, supported by transient thermal impedance character... Read More

Improved reliability of planar power interconnect with ceramic-based structure (2017)
Journal Article
Zhang, H., Li, J., Dai, J., Corfield, M., Liu, X., Liu, Y., …Johnson, C. M. (2018). Improved reliability of planar power interconnect with ceramic-based structure. IEEE Journal of Emerging and Selected Topics in Power Electronics, 6(1), doi:10.1109/JESTPE.2017.2758901. ISSN 2168-6785

This paper proposes an advanced Si3N4 ceramic-based structure with through vias designed and filled with brazing alloy as a reliable interconnect solution in planar power modules. Finite element (FE) modeling and simulation were first used to predict... Read More

Interconnect materials enabling IGBT modules to achieve stable short circuit failure behavior (2017)
Journal Article
Li, J., Yaqub, I., Corfield, M., & Johnson, C. M. (in press). Interconnect materials enabling IGBT modules to achieve stable short circuit failure behavior. IEEE Transactions on Components, Packaging, and Manufacturing Technology, 7(5), doi:10.1109/TCPMT.2017.2683202. ISSN 2156-3950

Insulated gate bipolar transistor (IGBT) modules, which can fail to stable short-circuit mode, have major applications in electricity network-related fields. Sn-3.5Ag solder joints and sintered Ag joints for the die attachment and Mo, Cu, Sn-3.5Ag, A... Read More

Damage evolution in Al wire bonds subjected to a junction temperature fluctuation of 30 K (2016)
Journal Article
Agyakwa, P., Yang, L., Arjmand, E., Evans, P., Corfield, M., & Johnson, C. M. (in press). Damage evolution in Al wire bonds subjected to a junction temperature fluctuation of 30 K. Journal of Electronic Materials, doi:10.1007/s11664-016-4519-0. ISSN 0361-5235

Ultrasonically bonded heavy Al wires subjected to a small junction temperature fluctuation under power cycling from 40°C to 70°C were investigated using a non-destructive three-dimensional (3-D) x-ray tomography evaluation approach. The occurrence of... Read More

Predicting lifetime of thick Al wire bonds using signals obtained from ultrasonic generator (2016)
Journal Article
Arjmand, E., Agyakwa, P., Corfield, M., Li, J., & Johnson, C. M. (2016). Predicting lifetime of thick Al wire bonds using signals obtained from ultrasonic generator. IEEE Transactions on Components, Packaging, and Manufacturing Technology, 6(5), doi:10.1109/TCPMT.2016.2543001. ISSN 2156-3985

Routine monitoring of the wire bonding process requires real-time evaluation and control of wire bond quality. In this paper, we present a nondestructive technique for detecting bond quality by the application of a semisupervised classification algor... Read More

A thermal cycling reliability study of ultrasonically bonded copper wires (2016)
Journal Article
Arjmand, E., Agyakwa, P. A., Corfield, M. R., Li, J., Mouawad, B., & Mark Johnson, C. (2016). A thermal cycling reliability study of ultrasonically bonded copper wires. Microelectronics Reliability, 59, doi:10.1016/j.microrel.2016.01.009. ISSN 0026-2714

In this work we report on a reliability investigation regarding heavy copper wires ultrasonically bonded onto active braze copper substrates. The results obtained from both a non-destructive approach using 3D X-ray tomography and shear tests showed n... Read More

Built-in reliability design of highly integrated solid-state power switches with metal bump interconnects (2014)
Journal Article
Li, J., Castellazzi, A., Dai, T., Corfield, M., Solomon, A. K., & Johnson, C. M. (2015). Built-in reliability design of highly integrated solid-state power switches with metal bump interconnects. IEEE Transactions on Power Electronics, 30(5), doi:10.1109/TPEL.2014.2357334

A stacked substrate–chip–bump–chip–substrate assembly has been demonstrated in the construction of power switch modules with high power density and good electrical performance. In this paper, special effort has been devoted to material selection and... Read More

Built-in reliability design of highly integrated solid-state power switches with metal bump interconnects (2014)
Journal Article
Li, J., Castellazzi, A., Dai, T., Corfield, M., Solomon, A. K., & Johnson, C. M. (2015). Built-in reliability design of highly integrated solid-state power switches with metal bump interconnects. IEEE Transactions on Power Electronics, 30(5), doi:10.1109/TPEL.2014.2357334. ISSN 0885-8993

A stacked substrate-chip-bump-chip-substrate assembly has been demonstrated in the construction of power switch modules with high power density and good electrical performance. In the present work, special effort has been devoted to material selectio... Read More

A non-destructive study of crack development during thermal cycling of Al wire bonds using x-ray computed tomography (2014)
Conference Proceeding
Agyakwa, P., Yang, L., Corfield, M., & Johnson, C. M. (2014). A non-destructive study of crack development during thermal cycling of Al wire bonds using x-ray computed tomography

This paper concerns the non-destructive visualisation of the evolution of damage within ultrasonically bonded alumini-um wires using three dimensional x-ray computed tomography. We demonstrate the potential to observe the progressive accumulation of... Read More