[1] [1] CASADY J B, JOHNSON R W. Status of silicon carbide (SiC) as a wide-bandgap semiconductor for high-temperature applications: a review［J］. Solid-State Electronics, 1996, 39(10): 1409-1422.

[2] [2] WEITZEL C E, PALMOUR J W, CARTER C H, et al. Silicon carbide high-power devices［J］. IEEE Transactions on Electron Devices, 1996, 43(10): 1732-1741.

[3] [3] KIMOTO T. Material science and device physics in SiC technology for high-voltage power devices［J］. Japanese Journal of Applied Physics, 2015, 54(4): 40103.1.

[4] [4] TSUNENOBU K, HEIJI W. Defect engineering in SiC technology for high-voltage power devices［J］. Applied Physics Express, 2020, 13(12): 120101-.

[5] [5] SKOWRONSKI M, HA S. Degradation of hexagonal silicon-carbide-based bipolar devices［J］. Journal of Applied Physics, 2006, 99(1): 011101.

[6] [6] SICHE D, KLIMM D, HLZEL T, et al. Reproducible defect etching of SiC single crystals［J］. Journal of Crystal Growth, 2004, 270(1/2): 1-6.

[7] [7] KALLINGER B, POLSTER S, BERWIAN P, et al. Threading dislocations in n- and p-type 4H-SiC material analyzed by etching and synchrotron X-ray topography［J］. Journal of Crystal Growth, 2011, 314(1): 21-29.

[8] [8] HASSAN J, HENRY A, MCNALLY P J, et al. Characterization of the carrot defect in 4H-SiC epitaxial layers［J］. Journal of Crystal Growth, 2010, 312(11): 1828-1837.

[9] [9] GAO Y, ZHANG Z H, BONDOKOV R, et al. The effect of doping concentration and conductivity type on preferential etching of 4H-SiC by molten KOH［C］//Proceedings of the Symposium on Silicon Carbide-Materials, Processing and Devices held at the 2004 MRS Spring Meeting, San Francisco, CA, F Apr 14-15, 2004.

[10] [10] YAKIMOVA R, HYLN A L, TUOMINEN M, et al. Preferential etching of SiC crystals［J］. Diamond and Related Materials, 1997, 6(10): 1456-1458.

[11] [11] SAKWE S A, MLLER R, WELLMANN P J. Optimization of KOH etching parameters for quantitative defect recognition in n- and p-type doped SiC［J］. Journal of Crystal Growth, 2006, 289(2): 520-526.

[12] [12] SYVJRVI M, YAKIMOVA R, HYLN A L, et al. Anisotropy of dissolution and defect revealing on SiC surfaces［J］. Journal of Physics: Condensed Matter, 1999, 11(49): 10041-10046.

[13] [13] ISHIKAWA Y, SUGAWARA Y, SAITOH H, et al. Characterization of surface defects of highly N-doped 4H-SiC substrates that produce dislocations in the epitaxial layer［J］. Materials Science Forum, 2010, 907(645/646/647/648): 351-354.

[14] [14] YAO Y Z, ISHIKAWA Y, SUGAWARA Y, et al. Molten KOH etching with Na2O2 additive for dislocation revelation in 4H-SiC epilayers and substrates［J］. Japanese Journal of Applied Physics, 2011, 50(7): 1-7.

[15] [15] YAO Y Z, ISHIKAWA Y, SUGAWARA Y, et al. Correlation between etch pits formed by molten KOH+Na2O2 etching and dislocation types in heavily doped n+-4H-SiC studied by X-ray topography［J］. Journal of Crystal Growth, 2013, 364: 7-10.

[16] [16] WEYHER J L, LAZAR S, BORYSIUK J, et al. Defect-selective etching of SiC［J］. Phys Status Solidi A-Appl Mat, 2005, 202(4): 578-583.

[17] [17] NA M, KANG I H, MOON J H, et al. Role of the oxidizing agent in the etching of 4H-SiC substrates with molten KOH［J］. Journal of the Korean Physical Society, 2016, 69(11): 1677-1682.

[18] [18] HA S, MIESZKOWSKI P, SKOWRONSKI M, et al. Dislocation conversion in 4H silicon carbide epitaxy［J］. Journal of Crystal Growth, 2002, 244(3/4): 257-266.

[19] [19] WU P, XU X, ZWIEBACK I, et al. Study of etching processes for SiC defect analysis［C］//2016 European Conference on Silicon Carbide & Related Materials (ECSCRM). September 25-29, 2016, Halkidiki, Greece. IEEE, 2017: 1.

[20] [20] CUI Y X, HU X B, XIE X J, et al. Threading dislocation classification for 4H-SiC substrates using the KOH etching method［J］. CrystEngComm, 2018, 20(7): 978-982.