當今全球面臨的能源危機正在敦促人們加速向更有效和更可靠的能源使用過渡。電力電子技術主要決定了通過開關設備進行電能轉換的效率和可靠性。因此，功率損耗和接面溫度的估計對半導體設備來說至關重要。由碳化矽（SiC）和氮化鎵（GaN）製成的寬帶隙功率（WBG）器件一直是這種轉換過程的先鋒趨勢。由於其出色的動態性能，用基於WBG的元件取代前身以矽為基礎的元件，可以提高工作溫度、開關頻率、崩潰電壓並降低功率損耗。然而，對氮化鎵器件而言，仍有許多挑戰，如缺乏雪崩能力，使其無法在大部分市場上廣泛採用。
本研究的目的是研究氮化鎵器件的電和熱能力，以提供一個關於其效率和可靠性的視角。詳細介紹了開關行為，並通過實驗進行了驗證。此外，還提出了通過多標準遺傳算法將仿真模型與測量結果進行擬合而得出的溫度相關參數的敏感性分析方法。最後，為了優化氮化鎵功率晶體管的效率性能，實現了一個基於氮化鎵的交流-直流轉換器的實驗室原型。

The energy crisis facing the globe nowadays is urging for accelerating the transition to more efficient and more reliable energy usage. Power electronics primarily determine the efficiency and reliability of electrical energy conversion via means of switching devices. Therefore, the estimation of the power loss and junction temperature has been of vital importance for the semiconductor devices. Wide bandgap (WBG) power devices made from Gallium Nitride (GaN) and Silicon Carbide (SiC) have been pioneering trends of such conversion process. Due to their outstanding dynamic performance, substituting WBG-based devices for entrenched Silicon-based predecessors can upgrade the operating temperatures, switching frequency, breakdown voltages and downgrade the power losses. However, specifically for GaN devices, there are still many challenges such as the absence of avalanche capacity, which prevents them from becoming broadly adopted in the bulk of the market.
The aim of this research is to study the electrical and thermal capabilities of GaN devices to provide a perspective on their efficiency and reliability. The switching behaviors are presented in details and verified with the experiments. In addition, a multi-criteria genetic algorithm-based method is proposed to adapt a simulation model to measurement data and then analyze the sensitivity of the parameters that rely on temperature. Finally, a laboratory prototype of GaN-based AC-DC converter is realized for the purpose of optimizing the efficiency performance of GaN power transistors.

[1] IEA, World Energy Outlook 2021, OECD Publishing, Paris, 2021, https://doi.org/10.1787/14fcb638-en.
[2] A. Lidow, M. De Rooij, J. Strydom, D. Reusch, and J. Glaser, GaN transistors for efficient power conversion. John Wiley & Sons, 2019.
[3] J. Wu, "The Development and Application of Semiconductor Materials," 2020 7th International Forum on Electrical Engineering and Automation (IFEEA), 2020, pp. 153-156, doi: 10.1109/IFEEA51475.2020.00039.
[4] M. Forouzesh, Y. P. Siwakoti, S. A. Gorji, F. Blaabjerg and B. Lehman, "Step-Up DC–DC Converters: A Comprehensive Review of Voltage-Boosting Techniques, Topologies, and Applications," in IEEE Transactions on Power Electronics, vol. 32, no. 12, pp. 9143-9178, Dec. 2017, doi: 10.1109/TPEL.2017.2652318.
[5] L. Esaki. “Highlights in Semiconductor Device Development,” JOURNAL OF RESEARCH of the National Bureau of Standards, 86(6), 565, 1981.
[6] R. K. Williams, M. N. Darwish, R. A. Blanchard, R. Siemieniec, P. Rutter and Y. Kawaguchi, "The Trench Power MOSFET: Part I—History, Technology, and Prospects," in IEEE Transactions on Electron Devices, vol. 64, no. 3, pp. 674-691, March 2017, doi: 10.1109/TED.2017.2653239.
[7] Nakagawa, A., Kawaguchi, Y., and Nakamura, K., “Silicon limit electrical characteristics of power devices and ICs, ” ISPSD, pp. 26-28, 2008.
[8] K. J. Chen et al., "GaN-on-Si power technology: Devices and applications," IEEE Transactions on Electron Devices, vol. 64, no. 3, pp. 779-795, 2017.
[9] N. Kaminski, "State of the art and the future of wide band-gap devices," 2009 13th European Conference on Power Electronics and Applications, 2009, pp. 1-9.
[10] M. Shur, "Wide bandgap semiconductor technology: State-of-the-art." Solid-State Electronics, vol. 155, no. 2, pp. 65-75, 2019.
[11] L. Shen, R. Barr, K. Shono, P. Smith, R. Lal and Y. Wu, "High Voltage GaN Power HEMTs Reliability," PCIM Asia 2019; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, 2019, pp. 1-4.
[12] J. Millán, P. Godignon, X. Perpiñà, A. Pérez-Tomás, and J. Rebollo, "A survey of wide bandgap power semiconductor devices," IEEE transactions on Power Electronics, vol. 29, no. 5, pp. 2155-2163, 2013.
[13] J. L. Hudgins, G. S. Simin, E. Santi and M. A. Khan, "An assessment of wide bandgap semiconductors for power devices," in IEEE Transactions on Power Electronics, vol. 18, no. 3, pp. 907-914, May 2003, doi: 10.1109/TPEL.2003.810840.
[14] F. Qi, Z. Wang, Y. Wu and P. Zuk, "900V GaN FETs in a 300kHz 2kW LLC Converter for High Input Voltage Applications," 2019 IEEE 7th Workshop on Wide Bandgap Power Devices and Applications (WiPDA), 2019, pp. 388-392, doi: 10.1109/WiPDA46397.2019.8998829.
[15] X. Huang, Z. Liu, Q. Li, and F. C. Lee, "Evaluation and application of 600 V GaN HEMT in cascode structure," IEEE Transactions on Power Electronics, vol. 29, no. 5, pp. 2453-2461, 2013.
[16] E. A. Jones, F. F. Wang, and D. Costinett, "Review of commercial GaN power devices and GaN-based converter design challenges," IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 4, no. 3, pp. 707-719, 2016.
[17] P. Murugapandiyan, V. R. Lakshmi, N. Ramkumar, P. Eswaran and M. Wasim, "Gan-based high-electron mobility transistors for high-power and high-frequency application: A review" in Innovations in Electronics and Communication Engineering, Singapore:Springer, April 2020.
[18] F. Semond, P. Lorenzini, N. Grandjean, and J. Massies, “High-electron-mobility AlGaN/GaN heterostructures grown on Si (111) by molecular-beam epitaxy,” Applied Physics Letters, 78(3), 335-337, 2001.
[19] T. Liu et al., "3-inch GaN-on-Diamond HEMTs With Device-First Transfer Technology," in IEEE Electron Device Letters, vol. 38, no. 10, pp. 1417-1420, Oct. 2017, doi: 10.1109/LED.2017.2737526.
[20] Haziq, M.; S. Falina, A. A. Manaf, H. Kawarada, M. Syamsul, "Challenges and Opportunities for High-Power and High-Frequency AlGaN/GaN High-Electron-Mobility Transistor (HEMT) Applications: A Review," Micromachines 2022, 13, 2133. https://doi.org/10.3390/mi13122133.
[21] K. Hirama, Y. Taniyasu and M. Kasu, "AlGaN/GaN high-electron mobility transistors with low thermal resistance grown on single-crystal diamond (111) substrates by metalorganic vapor-phase epitaxy", Appl. Phys. Lett., vol. 98, no. 16, pp. 1-4, Apr. 2011.
[22] A. Bindra, "Wide-Bandgap-Based Power Devices: Reshaping the power electronics landscape," in IEEE Power Electronics Magazine, vol. 2, no. 1, pp. 42-47, March 2015, doi: 10.1109/MPEL.2014.2382195.
[23] G. Laimer and J. W. Kolar, “Accurate measurement of the switching losses of ultra high switching speed coolmos power transistor/sic diode combination employed in unity power factor pwm rectifier systems,” in Proc. PCIM, 2002, pp. 14–16.
[24] J. Lutz, H. Schlagenotto, U. Scheuermann, and R. D. Doncker, Semiconductor Power Devices. Springer-Verlag, 2011.
[25] P. Brohlin and M. Beheshti, "Designing High-Density Power Solutions with GaN," in PCIM Europe 2018, pp. 1-5.
[26] E. A. Jones, F. F. Wang, and D. Costinett, "Review of commercial GaN power devices and GaN-based converter design challenges," IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 4, no. 3, pp. 707-719, 2016.
[27] A. Bindra, "Wide-Bandgap-Based Power Devices: Reshaping the power electronics landscape," in IEEE Power Electronics Magazine, vol. 2, no. 1, pp. 42-47, March 2015, doi: 10.1109/MPEL.2014.2382195.
[28] J. Gottschlich, M. Kaymak, M. Christoph and R. W. De Doncker, "A flexible test bench for power semiconductor switching loss measurements," 2015 IEEE 11th International Conference on Power Electronics and Drive Systems, 2015, pp. 442-448, doi: 10.1109/PEDS.2015.7203495.
[29] J. Magnien, L. Mitterhuber and E. Kraker, "Temperature Sensitive Electrical Parameter Sensing Unit for Early Failure Detection," 2019 25th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC), 2019, pp. 1-5, doi: 10.1109/THERMINIC.2019.8923688.
[30] H. Wang and F. Blaabjerg, "Power Electronics Reliability: State of the Art and Outlook," in IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 9, no. 6, pp. 6476-6493, Dec. 2021, doi: 10.1109/JESTPE.2020.3037161.
[31] L. Zhang, P. Liu, S. Guo and A. Q. Huang, "Comparative study of temperature sensitive electrical parameters (TSEP) of Si, SiC and GaN power devices," 2016 IEEE 4th Workshop on Wide Bandgap Power Devices and Applications (WiPDA), 2016, pp. 302-307, doi: 10.1109/WiPDA.2016.7799957.
[32] Y. Avenas, L. Dupont and Z. Khatir, "Temperature Measurement of Power Semiconductor Devices by Thermo-Sensitive Electrical Parameters—A Review," in IEEE Transactions on Power Electronics, vol. 27, no. 6, pp. 3081-3092, June 2012, doi: 10.1109/TPEL.2011.2178433.
[33] N. Mohan, T. Undeland, W. Robbins, “Power Electronics – Converters Applications, and Design”, text book published by Wiley.
[34] T. Kestler and M. -M. Bakran, "Expansion of the Junction Temperature Measurement via the Internal Gate Resistance to a wide range of Power Semiconductors," 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe), 2019, pp. P.1-P.9, doi: 10.23919/EPE.2019.8915530.
[35] S. Katoch, S.S. Chauhan and V. Kumar, "A review on genetic algorithm: past, present, and future," in Multimedia Tools and Applications, vol. 80, no. 4, pp. 8091–8126, Oct. 2021, doi:10.1007/s11042-020-10139-6.
[36] A. Lambora, K. Gupta and K. Chopra, "Genetic Algorithm- A Literature Review," 2019 International Conference on Machine Learning, Big Data, Cloud and Parallel Computing (COMITCon), 2019, pp. 380-384, doi: 10.1109/COMITCon.2019.8862255.
[37] "The European Parliament and of the Council, COMMISSION REGULATION (EU) 2019/424 laying down ecodesign requirements for servers and data storage products." https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32019R0424 (accessed March 18, 2019).
[38] D. Chakraborty, P. Das, and D. Srinivasan, "Coupled inductor based single-phase bridgeless PFC boost rectifier with auxiliary circuit assisted ZVS," in IEEE International Telecommunications Energy Conference, 2017: IEEE, pp. 410-416.
[39] C. N. M. Ho, R. T.-h. Li, and K. K.-M. Siu, "Active virtual ground—Bridgeless PFC topology," IEEE Transactions on Power Electronics, vol. 32, no. 8, pp. 6206-6218, 2016.
[40] X. Lin, F. Wang, and H. H. Iu, "A New Bridgeless High Step-up Voltage Gain PFC Converter with Reduced Conduction Losses and Low Voltage Stress," Energies, vol. 11, no. 10, p. 2640, 2018.
[41] W.-Y. Choi, J.-M. Kwon, E.-H. Kim, J.-J. Lee, and B.-H. Kwon, "Bridgeless boost rectifier with low conduction losses and reduced diode reverse-recovery problems," IEEE Transactions on industrial electronics, vol. 54, no. 2, pp. 769-780, 2007.
[42] L. Huber, Y. Jang, and M. M. Jovanovic, "Performance evaluation of bridgeless PFC boost rectifiers," IEEE transactions on power electronics, vol. 23, no. 3, pp. 1381-1390, 2008.
[43] K. Masumoto and M. Shoyama, "Comparative study about efficiency and switching noise of bridgeless PFC circuits," in 2012 International Conference on Renewable Energy Research and Applications (ICRERA), 2012: IEEE, pp. 1-5.
[44] J. C. Dias and T. B. Lazzarin, "A family of voltage-multiplier unidirectional single-phase hybrid boost PFC rectifiers," IEEE Transactions on Industrial Electronics, vol. 65, no. 1, pp. 232-241, 2017.
[45] Y. Chen and W.P. Dai, "Classification and comparison of BPFC Techniques: A review," Przegląd Elektrotechniczny, vol. 89, no. 2a, pp. 179-186, 2013.
[46] P. Brohlin and M. Beheshti, "Designing High-Density Power Solutions with GaN," in PCIM Europe 2018, pp. 1-5.
[47] Z. Liu, F. C. Lee, Q. Li, and Y. Yang, "Design of GaN-based MHz totem-pole PFC rectifier," IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 4, no. 3, pp. 799-807, 2016.
[48] L. Zhou, Y. Wu, J. Honea, and Z. Wang, "High-efficiency true bridgeless totem pole PFC based on GaN HEMT: Design challenges and cost-effective solution," in Proceedings of PCIM Europe 2015; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, 2015: VDE, pp. 1-8.
[49] M. Bhardwaj, S.-Y. Yu, Z. Ye, and S. Choudhury, "Improving light load power factor for GaN based Totem Pole bridgeless PFC using digital phase locked loop based vector cancellation & tracking error compensation," in 2018 IEEE Applied Power Electronics Conference and Exposition (APEC), 2018: IEEE, pp. 771-776.