All Outputs (42)

In-Service Diagnostics for Wire-Bond Lift-off and Solder Fatigue of Power Semiconductor Packages (2017)
Journal Article
Eleffendi, M. A., & Johnson, C. M. (2017). In-Service Diagnostics for Wire-Bond Lift-off and Solder Fatigue of Power Semiconductor Packages. IEEE Transactions on Power Electronics, 32(9), 7187-7198. https://doi.org/10.1109/TPEL.2016.2628705

Wire-bond lift-off and Solder fatigue are degradation mechanisms that dominate the lifetime of power semiconductor packages. Although their lifetime is commonly estimated at the design stage, based on mission profiles and Physics-of-Failure models, t... Read More about In-Service Diagnostics for Wire-Bond Lift-off and Solder Fatigue of Power Semiconductor Packages.

Damage Evolution in Al Wire Bonds Subjected to a Junction Temperature Fluctuation of 30K (2016)
Journal Article
Agyakwa, P., Yang, L., Arjmand, E., Evans, P., Corfield, M., & Johnson, C. M. (2016). Damage Evolution in Al Wire Bonds Subjected to a Junction Temperature Fluctuation of 30K. Journal of Electronic Materials, 45, 3659-3672. https://doi.org/10.1007/s11664-016-4519-0

© 2016, The Author(s). 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 appr... Read More about Damage Evolution in Al Wire Bonds Subjected to a Junction Temperature Fluctuation of 30K.

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), 814-821. https://doi.org/10.1109/TCPMT.2016.2543001

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 about Predicting Lifetime of Thick Al Wire Bonds Using Signals Obtained From Ultrasonic Generator.

Integrated motor drives: state of the art and future trends (2016)
Journal Article
Abebe, R., Vakil, G., Lo Calzo, G., Cox, T., Lambert, S., Johnson, C. M., …Mecrow, B. (2016). Integrated motor drives: state of the art and future trends. IET Electric Power Applications, 10(8), 757-771. https://doi.org/10.1049/iet-epa.2015.0506

With increased need for high power density, high efficiency and high temperature capabilities in aerospace and automotive applications, integrated motor drives (IMD) offers a potential solution. However, close physical integration of the converter an... Read More about Integrated motor drives: state of the art and future trends.

Hybrid HVDC circuit breaker with self-powered gate drives (2016)
Journal Article
Effah, F. B., Watson, A. J., Ji, C., Amankwah, E. K., Johnson, C. M., Davidson, C., & Clare, J. C. (2016). Hybrid HVDC circuit breaker with self-powered gate drives. IET Power Electronics, 9(2), 228-236. https://doi.org/10.1049/iet-pel.2015.0531

The ever increasing electric power demand and the advent of renewable energy sources have revived the interest in high-voltage direct current (HVDC) multi-terminal networks. However, the absence of a suitable circuit breaker or fault tolerant VSC st... Read More about Hybrid HVDC circuit breaker with self-powered gate drives.

Real-time deterministic power flow control through dispatch of distributed energy resources (2015)
Journal Article
Fazeli, A., Sumner, M., Johnson, C. M., & Christopher, E. (2015). Real-time deterministic power flow control through dispatch of distributed energy resources. IET Generation, Transmission and Distribution, 9(16), https://doi.org/10.1049/iet-gtd.2015.0182

Integration of intermittent renewable resources and mass electrification of heat and transport into the existing electricity network, with limited network asset reinforcement requires incorporation of intelligence in form of active management of flex... Read More about Real-time deterministic power flow control through dispatch of distributed energy resources.

Dependence of overcurrent failure modes of IGBT modules on interconnect technologies (2015)
Journal Article
Yaqub, I., Li, J., & Johnson, C. M. (2015). Dependence of overcurrent failure modes of IGBT modules on interconnect technologies. Microelectronics Reliability, 55(12), 2596-2605. https://doi.org/10.1016/j.microrel.2015.09.020

Insulated gate bipolar transistor (IGBT) modules which can fail to short circuit mode have great of applications in electricity network related fields. Single IGBT samples have been constructed with the standard Al wire bonding, flexible printed circ... Read More about Dependence of overcurrent failure modes of IGBT modules on interconnect technologies.

Design Tools for Rapid Multidomain Virtual Prototyping of Power Electronic Systems (2015)
Journal Article
Evans, P. L., Castellazzi, A., & Johnson, C. M. (2016). Design Tools for Rapid Multidomain Virtual Prototyping of Power Electronic Systems. IEEE Transactions on Power Electronics, 31(3), 2443-2455. https://doi.org/10.1109/TPEL.2015.2437793

The need for multidisciplinary virtual prototyping in power electronics has been well established, however, design tools capable of facilitating a rapid iterative virtual design process do not exist. A key challenge in developing such tools is identi... Read More about Design Tools for Rapid Multidomain Virtual Prototyping of Power Electronic Systems.

Application of Kalman Filter to Estimate Junction Temperature in IGBT Power Modules (2015)
Journal Article
Eleffendi, M. A., & Johnson, C. M. (2016). Application of Kalman Filter to Estimate Junction Temperature in IGBT Power Modules. IEEE Transactions on Power Electronics, 31(2), 1576-1587. https://doi.org/10.1109/TPEL.2015.2418711

Knowledge of instantaneous junction temperature is essential for effective health management of power converters, enabling safe operation of the power semiconductors under all operating conditions. Methods based on fixed thermal models are typically... Read More about Application of Kalman Filter to Estimate Junction Temperature in IGBT Power Modules.

Quantitative Microstructure Characterization of Ag Nanoparticle Sintered Joints for Power Die Attachment (2014)
Journal Article
Wang, Y., Li, J., Agyakwa, P., Johnson, C. M., & Li, S. (2014). Quantitative Microstructure Characterization of Ag Nanoparticle Sintered Joints for Power Die Attachment. Molecular Crystals and Liquid Crystals, 604(1), 11-26. https://doi.org/10.1080/15421406.2014.967647

© 2014 Copyright © Taylor & Francis Group, LLC. The samples of sintered Ag joints for power die attachments were prepared using paste of Ag nanoparticles at 240°C and 5 MPa for 3 to 17 minutes. Their microstructural features were quantitatively cha... Read More about Quantitative Microstructure Characterization of Ag Nanoparticle Sintered Joints for Power Die Attachment.

Mission Profile-Based Reliability Design and Real-Time Life Consumption Estimation in Power Electronics (2014)
Journal Article
Mussallam, M., Yin, C., Bailey, C., & Johnson, C. M. (2015). Mission Profile-Based Reliability Design and Real-Time Life Consumption Estimation in Power Electronics. IEEE Transactions on Power Electronics, 30(5), 2601-2613. https://doi.org/10.1109/TPEL.2014.2358555

Power electronics are efficient for conversion and conditioning of the electrical energy through a wide range of applications. Proper life consumption estimation methods applied for power electronics that can operate in real time under in-service mis... Read More about Mission Profile-Based Reliability Design and Real-Time Life Consumption Estimation in Power Electronics.

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), https://doi.org/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 about Built-in reliability design of highly integrated solid-state power switches with metal bump interconnects.

Calibration of a novel microstructural damage model for wire bonds (2014)
Journal Article
Yang, L., Agyakwa, P., & Johnson, C. (2014). Calibration of a novel microstructural damage model for wire bonds. IEEE Transactions on Device and Materials Reliability, 14(4), 989-994. https://doi.org/10.1109/TDMR.2014.2354739

In a previous paper, a new time-domain damage-based physics model was proposed for the lifetime prediction of wire bond interconnects in power electronic modules. Unlike cycle-dependent life prediction methodologies, this model innovatively incorpora... Read More about Calibration of a novel microstructural damage model for wire bonds.

Reliability of thick Al wire: a study of the effects of wire bonding parameters on thermal cycling degradation rate using non-destructive methods (2014)
Journal Article
Arjmand, E., Agyakwa, P. A., & 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, 54(9-10), https://doi.org/10.1016/j.microrel.2014.07.119

The effect of bonding parameters on the reliability of thick Al wire bond is investigated. Samples were prepared with 25 different designs with 5 different bonding parameters such as time, ultrasonic power, begin- force, end-force and touch-down step... Read More about Reliability of thick Al wire: a study of the effects of wire bonding parameters on thermal cycling degradation rate using non-destructive methods.

Bonding strength of multiple SiC die attachment prepared by sintering of Ag nanoparticles (2014)
Journal Article
Li, J., Johnson, C. M., Buttay, C., Sabbah, W., & Azzopardi, S. (2015). Bonding strength of multiple SiC die attachment prepared by sintering of Ag nanoparticles. Journal of Materials Processing Technology, 215, 299-308. https://doi.org/10.1016/j.jmatprotec.2014.08.002

3 mm × 3 mm dummy SiC dies with 100\200\200 nm thick Ti\W\Au metallization have simultaneously been attached using sintering of Ag nanoparticle paste on AlN-based direct bonded copper substrates with 5\0.1 μm thick NiP\Au finish. The effect of prepar... Read More about Bonding strength of multiple SiC die attachment prepared by sintering of Ag nanoparticles.

Integrated Half-Bridge Switch Using 70- ?m-Thin Devices and Hollow Interconnects (2014)
Journal Article
Solomon, A. K., Li, J., Castellazzi, A., & Johnson, C. M. (2015). Integrated Half-Bridge Switch Using 70- ?m-Thin Devices and Hollow Interconnects. IEEE Transactions on Industry Applications, 51(1), 556-566. https://doi.org/10.1109/TIA.2014.2334734

An application-oriented integration concept for a half-bridge switch assembly has been developed based on the latest generation 70- ?m-thin insulated gate bipolar transistors and diodes, which are rated at 600 V/200 A. This paper addresses the design... Read More about Integrated Half-Bridge Switch Using 70- ?m-Thin Devices and Hollow Interconnects.

Measurement of proton tunneling in short hydrogen bonds in single crystals of 3,5 pyridinedicarboxylic acid using nuclear magnetic resonance spectroscopy (2014)
Journal Article
Frantsuzov, I., Ford, S. J., Radosavljevic-Evans, I., Horsewill, A. J., Trommsdorff, H. P., & Johnson, M. R. (2014). Measurement of proton tunneling in short hydrogen bonds in single crystals of 3,5 pyridinedicarboxylic acid using nuclear magnetic resonance spectroscopy. Physical Review Letters, 113, https://doi.org/10.1103/PhysRevLett.113.018301

In this letter, we present NMR spin-lattice and relaxometry data for proton transfer in one of the shortest known N-H???O hydrogen bonds in a single crystal of 3,5 pyridinedicarboxylic acid (35PDCA). It is widely believed that proton transfer by quan... Read More about Measurement of proton tunneling in short hydrogen bonds in single crystals of 3,5 pyridinedicarboxylic acid using nuclear magnetic resonance spectroscopy.

Interdiffusion coefficients of binary multiphase systems with consideration of variation in Molar volumes (2014)
Journal Article
Li, J., Agyakwa, P., & Johnson, C. M. (2014). Interdiffusion coefficients of binary multiphase systems with consideration of variation in Molar volumes

This communication introduces a modification to the Wagner method to reveal and correct considerable systematic errors existing in the previously established analytical methods used to calculate the interdiffusion coefficients of binary multiphase sy... Read More about Interdiffusion coefficients of binary multiphase systems with consideration of variation in Molar volumes.

Suitable Thicknesses of Base Metal and Interlayer, and Evolution of Phases for Ag/Sn/Ag Transient liquid-phase Joints Used for Power Die Attachment (2014)
Journal Article
Li, J., Agyakwa, P., & Johnson, C. (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. https://doi.org/10.1007/s11664-013-2971-7

Real Si insulated gate bipolar transistors with conventional Ni/Ag metallization and dummy Si chips with thickened Ni/Ag metallization have both been bonded, at 250°C for 0 min, 40 min, and 640 min, to Ag foil electroplated with 2.7 μm and 6.8 μm thi... Read More about Suitable Thicknesses of Base Metal and Interlayer, and Evolution of Phases for Ag/Sn/Ag Transient liquid-phase Joints Used for Power Die Attachment.

Symmetry-breaking in the endofullerene H2O@C60 revealed in the quantum dynamics of ortho and para-water: a neutron scattering investigation (2014)
Journal Article
Goh, K. S., Jimenez-Ruiz, M., Johnson, M. R., Rols, S., Ollivier, J., Denning, M. S., …Horsewill, A. J. (2014). Symmetry-breaking in the endofullerene H2O@C60 revealed in the quantum dynamics of ortho and para-water: a neutron scattering investigation. Physical Chemistry Chemical Physics, 16(39), https://doi.org/10.1039/c4cp03272a

Inelastic neutron scattering (INS) has been employed to investigate the quantum dynamics of water molecules permanently entrapped inside the cages of C60 fullerene molecules. This study of the supramolecular complex, H2O@C60, provides the unique oppo... Read More about Symmetry-breaking in the endofullerene H2O@C60 revealed in the quantum dynamics of ortho and para-water: a neutron scattering investigation.