Pearl Agyakwa

Contact

• workPower Electronics & Machines Centre
  Jubilee Campus
  Wollaton Road
  Nottingham
  NG8 1BB
  UK
• pearl.agyakwa@nottingham.ac.uk

Biography

I am an experimental materials scientist with several years' experience in the characterisation of fine-scale microstructures relating to fatigue and creep, including aerospace and power plant structures. My current role within the PEMC group, which I've held since 2007, is centred on elucidating the degradation mechanisms and failure physics of power electronics packaging components, including ultrasonically bonded wire interconnects, solder and sintered nanosilver die-attachments. My expertise includes exploring and quantifying three-dimensional damage morphologies using 3D X-ray computed microtomography methodologies and mapping damage by using nanoindentation properties. I also explore alternative sensory modalities for perceiving materials properties and exploring materiality.

I am also an interdisciplinary researcher, interested in the humanistic aspects of materials and manufacturing. I am interested in how political, historical and cultural contexts influence what and how materials and manufacturing methods are used.

Expertise Summary

My expertise and research interests include: ultrasonic joining, microscopy & microstructures, 3D X-ray tomography, micromechanical properties, deformation & fracture, metallurgy, fatigue & creep, soldering, sintering and joining technologies, visualisation and image analysis, sound, sonification, arts-informed research design and community engaged research.

Recent Publications

• DAI, JINGRU, LI, JIANFENG, AGYAKWA, PEARL, CORFIELD, MARTIN and JOHNSON, CHRISTOPHER MARK, 2021. Reliability and Characterization of Nanosilver Joints Prepared by a Time-Reduced Sintering Process IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY. 21(4), 536-543
• DAI, JINGRU, LI, JIANFENG, AGYAKWA, PEARL, CORFIELD, MARTIN and JOHNSON, CHRISTOPHER MARK, 2018. Comparative Thermal and Structural Characterization of Sintered Nano-Silver and High-Lead Solder Die Attachments During Power Cycling IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY. 18(2), 256-265
• ARJMAND, E., AGYAKWA, P.A., CORFIELD, M., LI, J. and 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. (In Press.)
• AGYAKWA, P.A., YANG, L., ARJMAND, E., EVANS, P., CORFIELD, M. and JOHNSON, C.M., 2016. Damage Evolution in Al Wire Bonds Subjected to a Junction Temperature Fluctuation of 30 K Journal of Electronic Materials. 45(7), 3659–3672

• View all publications

• DAI, JINGRU, LI, JIANFENG, AGYAKWA, PEARL, CORFIELD, MARTIN and JOHNSON, CHRISTOPHER MARK, 2021. Reliability and Characterization of Nanosilver Joints Prepared by a Time-Reduced Sintering Process IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY. 21(4), 536-543
• DAI, JINGRU, LI, JIANFENG, AGYAKWA, PEARL, CORFIELD, MARTIN and JOHNSON, CHRISTOPHER MARK, 2018. Comparative Thermal and Structural Characterization of Sintered Nano-Silver and High-Lead Solder Die Attachments During Power Cycling IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY. 18(2), 256-265
• ARJMAND, E., AGYAKWA, P.A., CORFIELD, M., LI, J. and 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. (In Press.)
• AGYAKWA, P.A., YANG, L., ARJMAND, E., EVANS, P., CORFIELD, M. and JOHNSON, C.M., 2016. Damage Evolution in Al Wire Bonds Subjected to a Junction Temperature Fluctuation of 30 K Journal of Electronic Materials. 45(7), 3659–3672
• ARJMAND, E., AGYAKWA, P.A., CORFIELD, M., LI, JIANFENG, MOUAWAD, B. and JOHNSON, C.M., 2016. A thermal cycling reliability study of ultrasonically bonded copper wires Microelectronics Reliability. 59, 126-133
• ELEFFENDI, M.A., YANG, L, AGYAKWA, P.A. and JOHNSON, C.M., 2016. Quantification of cracked area in thermal path of high-power multi-chip modules using transient thermal impedance measurement
• ARJMAND, E., AGYAKWA, P.A. and JOHNSON, C.M., 2014. Reliability of thick Al wire: A study of the effects of wire bonding parameters on thermal cycling degradation rate using non-destructive methods Microelectronics Reliability.
• JIANFENG LI, PEARL AGYAKWA, PAUL EVANS, CHRISTOPHER MARK JOHNSON, YIMIN ZHAO, YIBO WU, KIM EVANS, 2014. Packaging / assembling technologies for a high performance SiC-based planar power module In: Greener Aviation Conference.
• J.F. LI, P.A. AGYAKWA, C.M. JOHNSON, 2014. Interdiffusion coefficients of binary multiphase systems with consideration of variation in Molar volumes International Journal of Materials Engineering and Technology. 12(1), 25-36
• YANG, L., AGYAKWA, P.A. and JOHNSON, C.M., 2014. Calibration of a novel microstructural damage model for wire bonds IEEE Transactions on Device and Materials Reliability. 14(4), 6891277
• WANG, Y., LI, J., AGYAKWA, P.A., JOHNSON, C.M. and LI, S., 2014. Quantitative microstructure characterization of Ag nanoparticle sintered joints for power die attachment Molecular Crystals and Liquid Crystals. 604(1), 11-26
• LI, J. F., AGYAKWA, P. A. and JOHNSON, C. M., 2014. Suitable Thicknesses of Base Metal and Interlayer, and Evolution of Phases for Ag/Sn/Ag Transient liquid-phase Joints Used for Power Die Attachment JOURNAL OF ELECTRONIC MATERIALS. 43(4), 983-995
• AGYAKWA, P. A., MARQUES, V. M. F., CORFIELD, M. R., LI, J. F., YANG, L. and JOHNSON, C. M., 2013. Room-Temperature Nanoindentation Creep of Thermally Cycled Ultrasonically Bonded Heavy Aluminum Wires JOURNAL OF ELECTRONIC MATERIALS. 42(3), 537-544
• AGYAKWA, P.A., YANG, L., CORFIELD, M. and JOHNSON, C.M., 2012. A non-destructive study of crack development during thermal cycling of Al wire bonds using x-ray computed tomography In: 8th International Conference on Integrated Power Electronics Systems, CIPS 2014.
• AGYAKWA, PA, CORFIELD, MR, YANG, L, LI, JF, MARQUES, VMF and JOHNSON, CM, 2011. Microstructural Evolution Of Ultrasonically Bonded High Purity Al Wire During Extended Range Thermal Cycling Microelectronics Reliability. 51(2), 406-415
• LI, J.F., AGYAKWA, P.A. and JOHNSON, C.M., 2011. Interfacial reaction in Cu/Sn/Cu system during the transient liquid phase soldering process Acta Materialia. 59(3), 1198-1211
• YANG, L., AGYAKWA, P. A. and JOHNSON, C. M., 2011. A time-domain physics-of-failure model for the lifetime prediction of wire bond interconnects MICROELECTRONICS RELIABILITY. 51(9-11), 1882-1886
• CASTELLAZZI, A., SOLOMON, A., AGYAKWA, P., LI, J., TRENTIN, A. and JOHNSON, C. M., 2010. High power density, low stray inductance, double sided cooled matrix-converter type switch In: 2010 International Power Electronics Conference (IPEC).
• MATTEY, N., SKURIAT, R., LI, J., AGYAKWA, P., EVANS, P. and JOHNSON, C.M., 2010. Thermal and mechanical design optimization of a pressure-mounted base-plate-less high temperature power module In: Electronic System-Integration Technology Conference (ESTC), 13-16 Sept. 2010.
• AGYAKWA, P.A., CORFIELD, M.R., LI, J.F., LOH, W.-S., LIOTTI, E., HOGG, S.C. and JOHNSON, C.M., 2010. Unusual observations in the wear-out of high-purity aluminium wire bonds under extended range passive thermal cycling IEEE Transactions on Device and Materials Reliability. 10(2), 254-262
• LI, J.F., AGYAKWA, P.A., JOHNSON, C.M., ZHANG, D., HUSSAIN, T. and MCCARTNEY, D.G., 2010. Characterization and solderability of cold sprayed Sn-Cu Coatings on Al and Cu substrates Surface and Coatings Technology. 204(9-10), 1395-1404
• SOLOMON, A., CASTELLAZZI, A., HOYLAND, R., AGYAKWA, P., JIANFENG LI and JOHNSON, C.M., 2009. A highly integrated high-voltage bi-directional switch In: ISDRS '09. International Semiconductor Device Research Symposium, 2009..
• HUA LU, RIDOUT, S., BAILEY, C., WEI SUN LOH, AGYAKWA, P. and JOHNSON, M., 2008. Computer simulation of crack propagation in power electronics module solder joints In: Electronic Packaging Technology & High Density Packaging, 28-31 July 2008.
• 2003. In: ANISOTROPIC BEHAVIOUR OF DAMAGED MATERIALS: Anisotropic creep and fracture behaviour of a 9CrMoNbV weld metal at 650 degrees C 9. 295-316
• HYDE, TH, SUN, W, AGYAKWA, PA, SHIPWAY, PH and WILLIAMS, JA, Anisotropic creep and fracture behaviour of a 9CrMoNbV weld metal at 650 degrees C ANISOTROPIC BEHAVIOUR OF DAMAGED MATERIALS. 9, 295-316