All Outputs (42)

Microstructural Response of Highly Porous Sintered Nano-silver Particle Die Attachments to Thermomechanical Cycling (2024)
Journal Article
Agyakwa, P. A., Robertson, S., Dai, J., Mouawad, B., Zhou, Z., Liu, C., & Johnson, C. M. (2024). Microstructural Response of Highly Porous Sintered Nano-silver Particle Die Attachments to Thermomechanical Cycling. Journal of Electronic Materials, 53, 1374–1398. https://doi.org/10.1007/s11664-023-10870-4

This paper deals with the performance of sintered nano-silver bonds used as wide-bandgap power module die attachment technology. The paper specifically explores the fine-scale microstructures of highly porous sintered attachments under power cycling... Read More about Microstructural Response of Highly Porous Sintered Nano-silver Particle Die Attachments to Thermomechanical Cycling.

Development and Validation of a Smart Architecture for Thyristor Valves (2023)
Journal Article
Sala, G., De Bonis, G., Costabeber, A., Tani, A., Johnson, C. M., & Clare, J. C. (2023). Development and Validation of a Smart Architecture for Thyristor Valves. IEEE Journal of Emerging and Selected Topics in Power Electronics, 11(4), 4068-4076. https://doi.org/10.1109/JESTPE.2023.3262344

A high voltage thyristor converter is realized by many valve sections, whose volume is approximately occupied for only the 10% by thyristors and for the 10% by the relevant gate drivers. The remaining 80% is taken by passive auxiliary circuits, neede... Read More about Development and Validation of a Smart Architecture for Thyristor Valves.

Reliability and Characterization of Nanosilver Joints Prepared by a Time-Reduced Sintering Process (2021)
Journal Article
Dai, J., Li, J., Agyakwa, P., Corfield, M., & Johnson, C. M. (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. https://doi.org/10.1109/TDMR.2021.3118323

This study investigates the power cycling reliability of nanosilver sintered joints formed by a time-reduced sintering process, designed for use on a die bonder. A range of sintering parameters, reflecting different levels of manufacturability, were... Read More about Reliability and Characterization of Nanosilver Joints Prepared by a Time-Reduced Sintering Process.

A GaN-HEMT Compact Model Including Dynamic RDSon Effect for Power Electronics Converters (2021)
Journal Article
Li, K., Evans, P. L., Johnson, C. M., Videt, A., & Idir, N. (2021). A GaN-HEMT Compact Model Including Dynamic RDSon Effect for Power Electronics Converters. Energies, 14(8), Article 2092. https://doi.org/10.3390/en14082092

In order to model GaN-HEMT switching transients and determine power losses, a compact model including dynamic RDSon effect is proposed herein. The model includes mathematical equations to represent device static and capacitance-voltage characteristic... Read More about A GaN-HEMT Compact Model Including Dynamic RDSon Effect for Power Electronics Converters.

Multi?frequency averaging (MFA) model of a generic electric vehicle powertrain suitable under variable frequency of averaging developed for remote operability (2020)
Journal Article
Sen, S., Evans, P. L., & Johnson, C. M. (2020). Multi?frequency averaging (MFA) model of a generic electric vehicle powertrain suitable under variable frequency of averaging developed for remote operability. IET Electrical Systems in Transportation, 10(3), 268-274. https://doi.org/10.1049/iet-est.2019.0043

© The Institution of Engineering and Technology 2020. Geographically distributed hardware-in-the-loop (HIL) testing has the potential to allow hybrid vehicle powertrain components (battery, motor drive, and engine) to be developed at geographically r... Read More about Multi?frequency averaging (MFA) model of a generic electric vehicle powertrain suitable under variable frequency of averaging developed for remote operability.

Accurate Measurement of Dynamic ON-state Resistance of GaN Devices under Reverse and Forward Conduction in High Frequency Power Converter (2020)
Journal Article
Li, K., Videt, A., Idir, N., Evans, P., & Johnson, M. (2020). Accurate Measurement of Dynamic ON-state Resistance of GaN Devices under Reverse and Forward Conduction in High Frequency Power Converter. IEEE Transactions on Power Electronics, 35(9), 9652-9662. https://doi.org/10.1109/TPEL.2019.2961604

Because of trapped charges in GaN transistor structure, device dynamic ON-state resistance RDSon is increased when it is operated in high frequency switched power converters, in which device is possibly operated by zero voltage switching (ZVS) to red... Read More about Accurate Measurement of Dynamic ON-state Resistance of GaN Devices under Reverse and Forward Conduction in High Frequency Power Converter.

10-kV SiC MOSFET Power Module With Reduced Common-Mode Noise and Electric Field (2019)
Journal Article
DiMarino, C. M., Mouawad, B., Johnson, C. M., Boroyevich, D., & Burgos, R. (2020). 10-kV SiC MOSFET Power Module With Reduced Common-Mode Noise and Electric Field. IEEE Transactions on Power Electronics, 35(6), 6050-6060. https://doi.org/10.1109/tpel.2019.2952633

The advancement of silicon carbide (SiC) power devices with voltage ratings exceeding 10 kV is expected to revolutionize medium- and high-voltage systems. However, present power module packages are limiting the performance of these unique switches. T... Read More about 10-kV SiC MOSFET Power Module With Reduced Common-Mode Noise and Electric Field.

Design and Experimental Validation of a Wire-Bond-Less 10-kV SiC MOSFET Power Module (2019)
Journal Article
DiMarino, C., Mouawad, B., Johnson, C. M., Wang, M., Tan, Y., Lu, G., …Burgos, R. (2020). Design and Experimental Validation of a Wire-Bond-Less 10-kV SiC MOSFET Power Module. IEEE Journal of Emerging and Selected Topics in Power Electronics, 8(1), 381-394. https://doi.org/10.1109/jestpe.2019.2944138

Wide bandgap (WBG) power devices with voltage ratings exceeding 10 kV have the potential to revolutionize medium-and high-voltage systems due to their high-speed switching and lower ON-state losses. However, the present power module packages are limi... Read More about Design and Experimental Validation of a Wire-Bond-Less 10-kV SiC MOSFET Power Module.

Three‐dimensional damage morphologies of thermomechanically deformed sintered nanosilver die attachments for power electronics modules (2019)
Journal Article
Agyakwa, P., Dai, J., Li, J., Mouawad, B., Yang, L., Corfield, M., & Johnson, C. (2019). Three‐dimensional damage morphologies of thermomechanically deformed sintered nanosilver die attachments for power electronics modules. Journal of Microscopy, 277(3), 140-153. https://doi.org/10.1111/jmi.12803

© 2019 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society. A time-lapse study of thermomechanical fatigue damage has been undertaken using three-dimensional X-ray computer tomography. Morp... Read More about Three‐dimensional damage morphologies of thermomechanically deformed sintered nanosilver die attachments for power electronics modules.

IEEE ITRW working group position paper: packaging and integration: unlocking the full potential of wide-bandgap devices (2018)
Journal Article
Johnson, M., Wilson, P. R., Empringham, L., & De Lillo, L. (2018). IEEE ITRW working group position paper: packaging and integration: unlocking the full potential of wide-bandgap devices. IEEE Power Electronics Magazine, 5(2), 26-33. https://doi.org/10.1109/mpel.2018.2822246

The International Technology Roadmap for Wide-Bandgap Power Semiconductors (ITRW) has four distinct technical working groups, each providing its own perspective on the technology and industrial drivers for the adoption of wide-bandgap (WBG) power sem... Read More about IEEE ITRW working group position paper: packaging and integration: unlocking the full potential of wide-bandgap devices.

Comparative Thermal and Structural Characterization of Sintered Nano-Silver and High-Lead Solder Die Attachments During Power Cycling (2018)
Journal Article
Dai, J., Li, J., Agyakwa, P., Corfield, M., & Johnson, C. M. (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. https://doi.org/10.1109/TDMR.2018.2825386

13.5 mm × 13.5 mm sintered nano-silver attachments for power devices onto AlN substrates were prepared at 250 ºC and a pressure of 10MPa for 5 minutes and compared with Pb5Sn solder joint die attachments under constant current power cycling with an i... Read More about Comparative Thermal and Structural Characterization of Sintered Nano-Silver and High-Lead Solder Die Attachments During Power Cycling.

Comparison of power cycling reliability of flexible PCB interconnect smaller/thinner and larger/thicker power devices with topside Sn-3.5Ag solder joints (2018)
Journal Article
Li, J., Dai, J., & Johnson, C. M. (2018). Comparison of power cycling reliability of flexible PCB interconnect smaller/thinner and larger/thicker power devices with topside Sn-3.5Ag solder joints. Microelectronics Reliability, 84, 55-65. https://doi.org/10.1016/j.microrel.2018.03.013

The power cycling reliability of flexible printed circuit board (PCB) interconnect smaller/thinner (ST) 9.5 mm × 5.5 mm × 0.07 mm and larger/thicker (LT) 13.5 mm × 13.5 mm × 0.5 mm single Si diode samples have been studied. With the assumption of cre... Read More about Comparison of power cycling reliability of flexible PCB interconnect smaller/thinner and larger/thicker power devices with topside Sn-3.5Ag solder joints.

Electrical Performance and Reliability Characterization of a SiC MOSFET Power Module With Embedded Decoupling Capacitors (2018)
Journal Article
O Brien, J., Yang, L., Li, K., Dai, J., Corfield, M., Harris, A., …Johnson, C. M. (2018). Electrical Performance and Reliability Characterization of a SiC MOSFET Power Module With Embedded Decoupling Capacitors. IEEE Transactions on Power Electronics, 33(12), 10594-10601. https://doi.org/10.1109/TPEL.2018.2809923

Integration of decoupling capacitors in SiC MOSFET modules is an advanced solution to mitigate the effect of parasitic inductance induced by module assembly interconnects. In this paper, the switching transient behavior is reported for a 1.2kV SiC MO... Read More about Electrical Performance and Reliability Characterization of a SiC MOSFET Power Module With Embedded Decoupling Capacitors.

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), 175-187. https://doi.org/10.1109/jestpe.2017.2758901

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 about Improved Reliability of Planar Power Interconnect With Ceramic-Based Structure.

Time-Efficient Sintering Processes to Attach Power Devices Using Nanosilver Dry Film (2017)
Journal Article
Dai, J., Li, J., Agyakwa, P., & Johnson, C. M. (2017). Time-Efficient Sintering Processes to Attach Power Devices Using Nanosilver Dry Film. Journal of Microelectronics and Electronic Packaging, 14(4), 140-149. https://doi.org/10.4071/imaps.521776

Pressure-assisted sintering processes to attach power devices using wet nanosilver pastes with time scales of minutes to a few hours have been widely reported. This paper presents our work on time-efficient sintering, using nanosilver dry film and an... Read More about Time-Efficient Sintering Processes to Attach Power Devices Using Nanosilver Dry Film.

Characterisation and modelling of gallium nitride power semiconductor devices dynamic on-state resistance (2017)
Journal Article
Li, K., Evans, P., & Johnson, M. (2018). Characterisation and modelling of gallium nitride power semiconductor devices dynamic on-state resistance. IEEE Transactions on Power Electronics, 33(6), 5262 - 5273. https://doi.org/10.1109/TPEL.2017.2730260

GaN-HEMTs suffer from trapping effects which increases device ON-state resistance (RDS(on)) above its theoretical value. This increase is a function of the applied DC bias when the device is in its OFF state, and the time which the device is biased f... Read More about Characterisation and modelling of gallium nitride power semiconductor devices dynamic on-state resistance.

SiC/GaN power semiconductor devices: a theoretical comparison and experimental evaluation under different switching conditions (2017)
Journal Article
Li, K., Evans, P., & Johnson, M. (in press). SiC/GaN power semiconductor devices: a theoretical comparison and experimental evaluation under different switching conditions. IET Electrical Systems in Transportation, https://doi.org/10.1049/iet-est.2017.0022

The conduction and switching losses of SiC and GaN power transistors are compared in this paper. Voltage rating of commercial GaN power transistors is less than 650V while that of SiC power transistors is less than 1200V. The paper begins with a theo... Read More about SiC/GaN power semiconductor devices: a theoretical comparison and experimental evaluation under different switching conditions.

Time-efficient sintering processes to attach power devices using nanosilver dry film (2017)
Journal Article
Dai, J., Li, J., Agyakwa, P., & Mark Johnson, C. (2017). Time-efficient sintering processes to attach power devices using nanosilver dry film. Additional Conferences (Device Packaging, HiTEC, HiTEN, & CICMT), 2017(HiTEN), 000207–000212. https://doi.org/10.4071/2380-4491.2017.hiten.207

Pressure-assisted sintering processes to attach power devices using wet nanosilver pastes with time scales of minutes to a few hours have been widely reported. This paper presents our work on time-efficient sintering, using nanosilver dry film and an... Read More about Time-efficient sintering processes to attach power devices using nanosilver dry film.

A Physical RC Network Model for Electrothermal Analysis of a Multichip SiC Power Module (2017)
Journal Article
Li, J., Castellazzi, A., Eleffendi, M. A., Gurpinar, E., Johnson, C. M., & Mills, L. (2018). A Physical RC Network Model for Electrothermal Analysis of a Multichip SiC Power Module. IEEE Transactions on Power Electronics, 33(3), 2494-2508. https://doi.org/10.1109/TPEL.2017.2697959

© 2017 IEEE. This paper is concerned with the thermal models which can physically reflect the heat-flow paths in a lightweight three-phase half-bridge two-level SiC power module with six MOSFETs and can be used for coupled electrothermal simulation.... Read More about A Physical RC Network Model for Electrothermal Analysis of a Multichip SiC Power Module.

Interconnect materials enabling IGBT modules to achieve stable short circuit failure behavior (2017)
Journal Article
Li, J., Yaqub, I., Corfield, M., & Johnson, C. M. (2017). Interconnect materials enabling IGBT modules to achieve stable short circuit failure behavior. IEEE Transactions on Components, Packaging, and Manufacturing Technology, 7(5), 734-744. https://doi.org/10.1109/TCPMT.2017.2683202

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 about Interconnect materials enabling IGBT modules to achieve stable short circuit failure behavior.