Realization and optimization of super-junction structures for high-efficiency silicon carbide power devices

  • Shijing Wang orcid

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Mingyu Zhang

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Jie Liang

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Leyi Tu

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Jian Li

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Zhiqian Gui

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Jiale Zhu

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China
  • Qian Wu

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China
  • Deqin He

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China
  • Haixin Qiu

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
  • Zhaoxiang Wang

    Shanghai AnBang Semi Equipment Co., Ltd., Shanghai 201208, China

    Shanghai BangXin Semi Technology Co., Ltd., Shanghai 201208, China
Article ID: 4128
DOI: https://doi.org/10.59400/mtr4128
Keywords: silicon carbide, super-junction trench, high-aspect-ratio, etch selectivity, side wall profile

Abstract

In this study, various silicon carbide (SiC) trench and via pattern etching processes are investigated, and high-aspect-ratio super-junction (SJ) structures are successfully fabricated. SiC SJ trenches are promising for ultra-high-voltage power device applications. Using a SiO₂ hard mask, SiC trenches with aspect ratios from 3:1 to 15:1 and depths exceeding 21 μm are prepared. Etch selectivity (SiC/SiO₂) is calculated based on the etched thicknesses of SiC and SiO₂ under the same process, and the selectivity can exceed 10:1 by optimizing hardware configuration and process parameters, especially gas combination and equipment settings. The significant effect of sidewall roughness transfers from the oxide hard mask to the SiC substrate is revealed. A smooth and optimized oxide hard mask sidewall is the key to reducing the final SiC sidewall roughness during pattern transfer. Full-wafer uniformity is improved by multiple tuning methods, including power ratio split, gas ratio split, temperature distribution control, and refined process parameters. Excellent uniformity is achieved: SiC trench critical dimension (CD) variation below 2%, SiC etch depth uniformity below 1%, and sidewall angles above 88° across the entire wafer. Long-term tool stability is verified over 10 consecutive months of etch rate monitoring with standard monitor wafers. The etch rate variation is controlled within 3% and uniformity below 2%, demonstrating reliable mass-production manufacturability of the SiC trench process.

Published
2026-06-03
How to Cite
Wang, S., Zhang, M., Liang, J., Tu, L., Li, J., Gui, Z., Zhu, J., Wu, Q., He, D., Qiu, H., & Wang, Z. (2026). Realization and optimization of super-junction structures for high-efficiency silicon carbide power devices. Materials Technology Reports, 4(1). https://doi.org/10.59400/mtr4128
Issue
Vol. 4 No. 1 (2026)
Section
Article

Copyright (c) 2026 Shijing Wang, Mingyu Zhang, Jie Liang, Leyi Tu, Jian Li, Zhiqian Gui, Jiale Zhu, Qian Wu, Deqin He, Haixin Qiu, Zhaoxiang Wang

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

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