Design Parameters Impact on Electrical Characteristics of 4H-SiC Thyristors with Etched Junction Termination Extension

Abstract:

4H-SiC thyristors are of particular interest in pulsed power applications due to their ability to block high voltages and transfer high current densities along with fast switching times. Here, we present a paper that demonstrates both (i) the impact of the design parameters on the blocking characteristics based on simulations taking into account the anisotropy of 4H-SiC and (ii) a critical comparison to real devices having equivalent epitaxial structural design. Simulations and measurements show that an etched junction termination extension (JTE) is suitable to design high-voltage SiC thyristors. Concerning breakdown voltage, the real devices data agree to simulations for junction termination extension thickness in the relevant region. Besides the actual JTE thickness and doping concentration, the presence of a relatively thin field-stop layer might explain the discrepancy between experiment and simulation.

• Periodical: Key Engineering Materials (Volume 1022)
• Pages: 1-8
• DOI: https://doi.org/10.4028/p-TfWv54
• Online since: September 2025
• Authors: Kamil Kotra*, Sigo Scharnholz, Ralf Hassdorf, Milan Zuvic, Klaus Hoffmann
• Keywords: 4H-SiC, Etched JTE, Junction Termination, Pulsed Power, TCAD Simulation, Thyristor

References

[1] H. O'Brien, A. Ogunniyi, S.H. Ryu, T. Tsoi, S.B. Bayne, "High-voltage silicon carbide thyristors on n-doped epi for pulsed power", in Proc. IEEE Int. Pulsed Power Conference, Denver, CO, USA, 2021, pp.1-4.

DOI: 10.1109/ppc40517.2021.9733054

[2] Z. Li, K. Zhou, L. Zhang, X. Xu, L. Li, J. Li, G. Dai, "A simple multistep etched termination technique for 4H-SiC GTO thyristors", Solid State Electronics, vol. 151, 2019, pp.1-5.

DOI: 10.1016/j.sse.2018.10.013

[3] P. Godignon, J. Montserrat, J. Rebello, D. Planson, "Edge terminations for 4H-SiC power devices: A critical issue", Materials Science Forum, vol. 1062, 2022, pp.570-575.

DOI: 10.4028/p-lom714

[4] G. Pâques, S. Scharnholz, N. Dheilly, D. Planson, R.W. De Doncker, "High-voltage 4H-SiC thyristors with a graded etched junction termination extension", IEEE Electron Device Letters, vol. 32, no. 10, 2011, pp.1421-1423.

DOI: 10.1109/led.2011.2163055

[5] B.J. Baliga, "Fundamentals of Power Semiconductor Devices", Springer Science, New York, NY, USA, 2008.

[6] SentaurusTM Device User Guide, version S-2021-06, Synopsys Inc., 2021, p.445.

[7] T. Hatakeyama, J. Nishio, C. Ota, T. Shinohe, "Physical modeling and scaling properties of 4H-SiC power devices", Proc. IEEE Int. Conf. on Simulation of Semiconductor Processes and Devices, Tokyo, Japan, 2005, pp.171-174.

DOI: 10.1109/sispad.2005.201500

[8] T. Kimoto, J.A. Cooper, "Fundamentals of Silicon Carbide Technology: Growth, Characterization, Devices, and Applications", John Wiley & Sons Singapore Pte. Ltd, 2014, pp.11-30.

DOI: 10.1002/9781118313534

[9] S. Scharnholz, R. Hassdorf, J. Grau, K. Kotra, M. Zuvic, B. Vergne, unpublished results.

[10] T. Kimoto, "High-voltage SiC power devices for improved energy efficiency", Proc. Jpn. Acad., no. 4, 2022, pp.161-189.