Publications

Patents|Book Chapters|Journal Publications|Conference Publications|Other

Patent families
  1. P. Ward, N. Lophitis, T. Trajkovic, F. Udrea, “High voltage semiconductor device with reduced peak electric field in active and termination areas of the device”, US10157979B2, 2018
  2. P. Ward, N. Lophitis, T. Trajkovic, F. Udrea, “High Voltage Semiconductor Devices,” US20170243937, 2017. WO2016042330, 2016,
  3. N. Lophitis, F. Udrea, U. Vemulapati, I Nistor, M. Arnold, J. Vobecky, M Rahimo, “Reverse conducting power semiconductor device”, US15078602, 2015, EP20150160264, 2016, JP2016056807A, 2016,  KR20160034475A, 2016, CN 201610442461, 2016, US009543305, 2017.
Book chapters
  1. N. Lophitis, A. Arvanitopoulos, S. Perkins, and M. Antoniou, “TCAD Device Modelling and Simulation of Wide Bandgap Power Semiconductors,” in Disruptive Wide Bandgap Semiconductors, Related Technologies, and Their Applications, Y. K. Sharma, Ed. Rijeka: InTech, 2018. doi: 10.5772/intechopen.76062
Journal Publications
  1. R. Stocker, A. Mumtaz, Paramjeet, M. Braglia, and N. Lophitis, “Universal Li-Ion Cell Electro-Thermal Model,” IEEE Transactions on Transportation Electrification, p. (In-press), 2020, doi: 10.1109/TTE.2020.2986606.
  2. A. Arvanitopoulos, M. Antoniou, M. R. Jennings, S. Perkins, K. N. Gyftakis, P. Mawby, and N. Lophitis, “A Defects-Based Model on the Barrier Height Behavior in 3C-SiC-on-Si Schottky Barrier Diodes,” IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 8, no. 1, pp. 54–65, Mar. 2020, doi: 10.1109/JESTPE.2019.2942714.
  3. A. K. Tiwari, M. Antoniou, N. Lophitis, S. Perkin, T. Trajkovic, and F. Udrea, “Retrograde p-Well for 10-kV Class SiC IGBTs,” IEEE Transactions on Electron Devices, vol. 66, no. 7, pp. 3066–3072, Jul. 2019, doi: 10.1109/TED.2019.2918008.
  4. A. Arvanitopoulos, M. Antoniou, S. Perkins, M. Jennings, M. B. Guadas, K. N. Gyftakis, and N. Lophitis, “On the Suitability of 3C-Silicon Carbide as an Alternative to 4H-Silicon Carbide for Power Diodes,” IEEE Transactions on Industry Applications, vol. 55, no. 4, pp. 4080–4090, Jul. 2019, doi: 10.1109/TIA.2019.2911872.
  5. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis, “A New Approach for Broken Rotor Bar Detection in Induction Motors Using Frequency Extraction in Stray Flux Signals,” IEEE Transactions on Industry Applications, vol. 55, no. 4, pp. 3501–3511, Jul. 2019, doi: 10.1109/TIA.2019.2905803.
  6. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis, “On the broken rotor bar diagnosis using time–frequency analysis: ‘Is one spectral representation enough for the characterisation of monitored signals?,’” IET Electric Power Applications, vol. 13, no. 7, pp. 932–942, Jul. 2019, doi: 10.1049/iet-epa.2018.5512.
  7. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis, “FEM approach for diagnosis of induction machines’ non-adjacent broken rotor bars by short-time Fourier transform spectrogram,” The Journal of Engineering, vol. 2019, no. 17, pp. 4566–4570, Jun. 2019, doi: 10.1049/joe.2018.8240.
  8. M. Antoniou, N. Lophitis, F. Udrea, M. Rahimo, U. Vemulapati, C. Corvasce, and U. Badstuebner, “Deep p-Ring Trench Termination: An Innovative and Cost-Effective Way to Reduce Silicon Area,” IEEE Electron Device Letters, vol. 40, no. 2, pp. 177–180, Feb. 2019, doi: 10.1109/LED.2018.2890702.
  9. N. Lophitis, M. Antoniou, U. Vemulapati, J. Vobecky, U. Badstuebner, T. Wikstroem, T. Stiasny, M. Rahimo, and F. Udrea, “Optimal Gate Commutated Thyristor Design for Bi-Mode Gate Commutated Thyristors Underpinning High, Temperature Independent, Current Controllability,” IEEE Electron Device Letters, vol. 39, no. 9, pp. 1342–1345, Sep. 2018. doi: 10.1109/LED.2018.2847050
  10. M. Antoniou, N. Lophitis, F. Udrea, F. Bauer, U. R. Vemulapati, and U. Badstuebner, “On the Investigation of the ‘Anode Side’ SuperJunction IGBT Design Concept,” IEEE Electron Device Letters, vol. 38, no. 8, pp. 1063–1066, Aug. 2017. doi: 10.1109/LED.2017.2718619
  11. Arvanitopoulos, N. Lophitis, K. N. Gyftakis, S. Perkins, and M. Antoniou, “Validated physical models and parameters of bulk 3C-SiC aiming for credible Technology Computer Aided Design ( TCAD ) simulation,” IOP Semiconductor Science and Technology, vol. 32, no. 10, p. 104009, Oct. 2017. doi: 10.1088/1361-6641/aa856b
  12. N. Lophitis, M. Antoniou, F. Udrea, U. Vemulapati, M. Arnold, I. Nistor, J. Vobecky, M. Rahimo, F. Udrea, U. Vemulapati, M. Arnold, I. Nistor, J. Vobecky, and M. Rahimo, “New Bi-Mode Gate-Commutated Thyristor Design Concept for High-Current Controllability and Low ON-State Voltage Drop,” IEEE Electron Device Letters, vol. 37, no. 4, pp. 467–470, Apr. 2016. doi: 10.1109/LED.2016.2533572
  13. M. Antoniou, N. Lophitis, F. Bauer, I. Nistor, M. Bellini, M. Rahimo, G. Amaratunga, and F. Udrea, “Novel Approach Toward Plasma Enhancement in Trench-Insulated Gate Bipolar Transistors,” IEEE Electron Device Letters, vol. 36, no. 8, pp. 823–825, Aug. 2015. doi: 10.1109/LED.2015.2433894
  14. N. Lophitis, M. Antoniou, F. Udrea, U. Vemulapati, M. Arnold, I. Nistor, J. Vobecky, and M. Rahimo, “Improving Current Controllability in Bi-Mode Gate Commutated Thyristors,” IEEE Transactions on Electron Devices, vol. 62, no. 7, pp. 2263–2269, Jul. 2015. doi: 10.1109/TED.2015.2428994
  15. N. Lophitis, J. Vobecky, M. Arnold, T. Wikström, I. Nistor, M. Antoniou, and F. Udrea, “Parameters influencing the maximum controllable current in gate commutated thyristors,” IET Circuits, Devices & Systems, vol. 8, no. 3, pp. 221–226, May 2014. doi: 10.1049/iet-cds.2013.0217
  16. N. Lophitis, M. Antoniou, F. Udrea, F. D. Bauer, I. Nistor, M. Arnold, T. Wikstrom, and J. Vobecky, “The Destruction Mechanism in GCTs,” IEEE Transactions on Electron Devices, vol. 60, no. 2, pp. 819–826, Feb. 2013. doi: 10.1109/TED.2012.2235442
  17. N. Lophitis, M. Antoniou, F. Udrea, I. Nistor, M. T. Rahimo, M. Arnold, T. Wikstroem, and J. Vobecky, “Gate Commutated Thyristor With Voltage Independent Maximum Controllable Current,” IEEE Electron Device Letters, vol. 34, no. 8, pp. 954–956, Aug. 2013. doi: 10.1109/LED.2013.2267552
Papers in international conferences
  1. M. Antoniou, N. Lophitis, F. Udrea, C. Corvasce, and L. De-Michielis, “The p-ring Trench Schottky IGBT: A solution towards latch-up immunity and an enhanced safe-operating area,” in IEEE International Symposium on Power Semiconductor Devices & IC’s (ISPSD), 2020, p. (accepted).
  2. U. Vemulapati, T. Stiasny, T. Wikström, N. Lophitis, and F. Udrea, “Integrated Gate Commutated Thyristor : From Trench to Planar,” in IEEE International Symposium on Power Semiconductor Devices & IC’s (ISPSD), 2020, p. (accepted).
  3. R. Stocker, A. Mumtaz, and N. Lophitis, “Design-of-Experiments Analysis of Li-Ion Cell Capacity Fading in High Temperature Automotive Conditions,” in 2019 Electric Vehicles International Conference (EV), Oct. 2019, doi: 10.1109/EV.2019.8893026.
  4. A. Arvanitopoulos, F. Li, M. R. Jennings, S. Perkins, K. N. Gyftakis, M. Antoniou, P. Mawby, and N. Lophitis, “Experimental Investigation and Verification of Traps affecting the performance of 3C-SiC-on-Si Schottky Barrier Diodes,” in 2019 IEEE Energy Conversion Congress and Exposition (ECCE), Sep. 2019, pp. 1941–1947, doi: 10.1109/ECCE.2019.8912232.
  5. S. Perkins, M. Antoniou, A. K. Tiwari, A. Arvanitopoulos, K. N. Gyftakis, N. Lophitis, T. Trajkovic, F. Udrea, and N. Lophitis, “Optimal edge termination for high oxide reliability aiming 10kV SiC n-IGBTs,” in 12th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED 2019), 2019, p. (accepted)
  6. Amit K. Tiwari, M. Antoniou, S. Perkin, N. Lophitis, T. Trajkovic, and F. Udrea, “On the robustness of ultra-high voltage 4H-SiC IGBTs with an optimized retrograde p-well,” in 12th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED 2019), 2019, p. (accepted)
  7. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, and K. N. Gyftakis, “Frequency Extraction of Current Signal Spectral Electrical Faults in Induction Motors,” in 12th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED 2019), 2019, p. (Accepted)
  8. A. Arvanitopoulos, M. Antoniou, F. Li, M. R. Jennings, S. Perkins, K. N. Gyftakis, and N. Lophitis, “Viable 3C-SiC-on-Si MOSFET design disrupting current Material Technology Limitations,” in 12th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED 2019), 2019, p. (accepted)
  9. A. K. Tiwari, F. Udrea, N. Lophitis, and M. Antoniou, “Operation of ultra-high voltage (>10kV) SiC IGBTs at elevated temperatures: benefits & constraints,” in 2019 31st International Symposium on Power Semiconductor Devices and ICs (ISPSD), May 2019, pp. 175–178, doi: 10.1109/ISPSD.2019.8757586.
  10. S. Perkins, M. Antoniou, A. K. Tiwari, A. Arvanitopoulos, T. Trajkovic, F. Udrea, and N. Lophitis, “>10kV 4H-SiC n-IGBTs for Elevated Temperature Environments,” in The 14th International Seminar on Power Semiconductors (ISPS 2018), 2018
  11. A. Arvanitopoulos, S. Perkins, M. Jennings, M. Antoniou, K. N. Gyftakis, and N. Lophitis, “Carrier Transport mechanisms contributing to the sub-threshold current in 3C-SiC Schottky Barrier Diodes,” in 2018 IEEE 1st Workshop on Wide Bandgap Power Devices and Applications in Asia (WiPDA-Asia), 2018
  12. R. Stocker, N. Lophitis, and A. Mumtaz, “Development and Verification of a Distributed Electro-Thermal Li-Ion Cell Model,” in IECON 2018 – 44th Annual Conference of the IEEE Industrial Electronics Society, 2018, pp. 2044–2049. doi: 10.1109/IECON.2018.8591633
  13. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, and K. N. Gyftakis, “FEM Study of Induction Machines Suffering from Rotor Electrical Faults Using Stray Flux Signature Analysis,” in 2018 XIII International Conference on Electrical Machines (ICEM), 2018, pp. 1861–1867. doi: 10.1109/ICELMACH.2018.8506707
  14. A. Arvanitopoulos, M. Antoniou, M. R. Jennings, F. Li, S. Perkins, K. N. Gyftakis, and N. Lophitis “On the development of the 3C-SiC Power Law and its applicability for the Evaluation of Termination Structures,” in The 14th International Seminar on Power Semiconductors (ISPS 2018), 2018
  15. S. Perkins, A. Arvanitopoulos, K. N. Gyftakis, and N. Lophitis, “On the Static Performance of Commercial GaN-on- Si Devices at Elevated Temperatures,” in 2018 IEEE 1st Workshop on Wide Bandgap Power Devices and Applications in Asia (WiPDA-Asia), 2018
  16. A. K. Tiwari, M. Antoniou, N. Lophitis, S. Perkins, and T. Trakovic, “Performance improvement of > 10kV SiC IGBTs with retrograde p-well,” in The 12th European Conference on Silicon Carbide and Related Materials (ECSCRM), 2018
  17. P. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis, “FEM Approach for Diagnosis of Induction Machines’ Non-Adjacent Broken Rotor Bars by STFT Spectrogram,” in 2018 IET 9th International Conference on Power Electronics, Machines & Drives (PEMD), 2018
  18. P. A. Panagiotou, I. Arvanitakis, N. Lophitis, J. A. Antonino-Daviu, and K. N. Gyftakis, “Analysis of Stray Flux Spectral Components in Induction Machines under Rotor Bar Breakages at Various Locations,” in 2018 XIII International Conference on Electrical Machines (ICEM), 2018, pp. 2345–2351. doi: 10.1109/ICELMACH.2018.8506929
  19. P. A. Panagiotou, K. N. Gyftakis, N. Lophitis, M. D. McCulloch, and D. A. Howey, “Investigation of traction motor windings’ insulation capacitance at switching frequencies under accelerated thermal stress,” in 2017 IEEE 11th International Symposium on Diagnostics for Electrical Machines, Power Electronics and Drives (SDEMPED), 2017, pp. 537–543. doi: 10.1109/DEMPED.2017.8062407
  20. A. Arvanitopoulos, S. Perkins, K. N. Gyftakis, M. Antoniou, and N. Lophitis, “3C-SiC material parameters for accurate TCAD modeling and simulation,” in The 10th International Conference on Silicon Epitaxy and heterostructures – ICSI10, 2017, pp. 115–116
  21. S. Perkins, A. Arvanitopoulos, K. N. Gyftakis, and N. Lophitis, “A comprehensive comparison of the static performance of commercial GaN-on-Si devices,” in 2017 IEEE 5th Workshop on Wide Bandgap Power Devices and Applications (WiPDA), 2017, pp. 177–184.
    doi: 10.1109/WiPDA.2017.8170543
  22. M. Charalampidi, M. Hammond, N. Hadjipavlou, and N. Lophitis, “A Content and Language Integrated Learning (CLIL) Project: Opportunities and Challenges in the Context of Heritage Language Education,” in The European Conference on Language Learning 2017, 2017
  23. K. N. Gyftakis, P. A. Panagiotou, N. Lophitis, D. A. Howey, and M. D. McCulloch, “Breakdown resistance analysis of traction motor winding insulation under thermal ageing,” in 2017 IEEE Energy Conversion Congress and Exposition (ECCE), 2017, pp. 5819–5825.
    doi: 10.1109/ECCE.2017.8096964
  24. A. Arvanitopoulos, N. Lophitis, S. Perkins, K. N. Gyftakis, M. Belanche Guadas, and M. Antoniou, “Physical parameterisation of 3C-Silicon Carbide (SiC) with scope to evaluate the suitability of the material for power diodes as an alternative to 4H-SiC,” in 2017 IEEE 11th International Symposium on Diagnostics for Electrical Machines, Power Electronics and Drives (SDEMPED), 2017, pp. 565–571. doi: 10.1109/DEMPED.2017.8062411
  25. N. Lophitis, M. Antoniou, F. Udrea, U. Vemulapati, M. Arnold, M. Rahimo, and J. Vobecky, “4.5 kV Bi-mode Gate Commutated Thyristor design with High Power Technology and shallow diode-anode,” in 2016 28th International Symposium on Power Semiconductor Devices and ICs (ISPSD), 2016, pp. 371–374. doi: 10.1109/ISPSD.2016.7520855
  26. U. Vemulapati, M. Arnold, M. Rahimo, J. Vobecky, T. Stiasny, N. Lophitis, and F. Udrea, “An experimental demonstration of a 4.5 kV Bi-mode Gate Commutated Thyristor (BGCT),” in 2015 IEEE 27th International Symposium on Power Semiconductor Devices & IC’s (ISPSD), 2015, pp. 109–112. doi: 10.1109/ISPSD.2015.7123401
  27. M. Antoniou, N. Lophitis, F. Udrea, F. Bauer, I. Nistor, M. Bellini, and M. Rahimo, “Experimental demonstration of the p-ring FS+ Trench IGBT concept: A new design for minimizing the conduction losses,” in 2015 IEEE 27th International Symposium on Power Semiconductor Devices & IC’s (ISPSD), 2015, vol. 2015–June, pp. 21–24. doi: 10.1109/ISPSD.2015.7123379
  28. N. Lophitis, M. Antoniou, F. Udrea, I. Nistor, M. Arnold, T. Wikstrom, J. Vobecky, and M. Rahimo, “The Stripe Fortified GCT: A new GCT design for maximizing the controllable current,” in 2014 IEEE 26th International Symposium on Power Semiconductor Devices & IC’s (ISPSD), 2014, pp. 123–126. doi: 10.1109/ISPSD.2014.6855991
  29. N. Lophitis, M. Antoniou, F. Udrea, I. Nistor, M. Arnold, T. Wikström, and J. Vobecky, “Optimization of Parameters influencing the Maximum Controllable Current in Gate Commutated Thyristors,” in International Seminar on Power Semiconductors (ISPS), 2012.
  30. N. Lophitis, M. Antoniou, F. Udrea, I. Nistor, M. Arnold, T. Wikstrom, and J. Vobecky, “Experimentally validated three dimensional GCT wafer level simulations,” in 2012 IEEE 24th International Symposium on Power Semiconductor Devices and ICs (ISPSD), 2012, pp. 349–352. doi: 10.1109/ISPSD.2012.6229093
  31. N. Lophitis, M. Antoniou, F. Udrea, T. Wikstrom, and I. Nistor, “Turn-off failure mechanism in large area IGCTs,” in CAS 2011 Proceedings (2011 International Semiconductor Conference), 2011, vol. 2, pp. 361–364. doi: 10.1109/SMICND.2011.6095817
Other conference and workshop posters and oral presentations
  1. Arvanitopoulos, S. Perkins, M. Jennings, M. Antoniou, F. Li, K. Gyftakis and N. Lophitis, “Carrier Transport mechanisms contributing to the sub-threshold current in 3C-SiC-on-Si Schottky Barrier Diodes”, EPSRC Power Electronics Centre Annual Conference, 2018.
  2. S. Perkins, A. Arvanitopoulos, K. Gyftakis and N. Lophitis, “The Static Performance of Commercial GaN-on-Si Devices at Elevated Temperatures”, EPSRC Power Electronics Centre Annual Conference, 2018.
  3. S. Perkins, M. Antoniou, A. Tiwari, A. Arvanitopoulos, T. Trajkovic, F. Udrea and N. Lophitis, “>10kV 4H-SiC n-IGBTs for Elevated Temperature Environments”, EPSRC Power Electronics Centre Annual Conference, 2018.
  4. P. M. Gammon, P. A. Mawby, N. Lophitis, N. Wright, A. O’Neill, F. Udrea, “Underpinning Power Electronics 2017 – Switch Optimisation Theme”, EPSRC Power Electronics Centre Annual Conference, 2017.
  5. R. Stocker, A. Mumtaz, N. Lophitis, “Understanding Ageing in Li-ion Cells : an Enabler for Effective Grid Interaction Strategies,” IEEE PES Manchester Electrical Energy and Power Systems (MEEPS), 2016.
  6. N. Lophitis, F. Udrea, I Nistor, “Three dimensional GCT wafer level simulations”, EPSRC Power Electronics Centre Launch event, 2013.