-
GaN based Schottky barrier diode (SBD) offer advantages including high power density, high conversion efficiency, and excellent switching characteristics. During heteroepitaxial growth of GaN, a high density of threading dislocations is inevitably introduced, which can degrade device reliability. This paper reports a low dislocation density N+/N- GaN quasi-vertical SBD fabricated on a freestanding GaN substrate. The characterization results of high-resolution X-ray diffraction and atomic force microscopy demonstrate that the high-quality epitaxial layer with a total dislocation density of 1.01×108 cm-2 and a root mean square surface roughness of 0.149 nm has been achieved on a freestanding GaN substrate. Devices prepared based on high-quality epitaxial layer exhibit an ultra-low leakage current density of 10-5 A/cm2 at a reverse voltage of -5V, without employing any edge termination structures, field plates, or plasma treatment. Compared with the devices prepared on sapphire substrates using identical processes, the reverse leakage current demonstrates a reduction by four orders of magnitude. The experimental results show that the quasi-vertical GaN based SBD fabricated on a freestanding GaN substrate significantly reduces reverse leakage current and substantially enhances the overall electrical performance of the device. By employing micro-microscope, leakage current in quasi-vertical SBDs was identified to be primarily localized at the anode edges, and the underlying leakage mechanism was elucidated. Finally, temperature-dependent measurements demonstrated the device maintains a leakage current below 10-3 A/cm2 at 100℃, confirming the potential of quasi-vertical SBD on freestanding GaN substrate for practical applications.
-
Keywords:
- freestanding gallium nitride /
- dislocation density /
- quasi-vertical schottky diode /
- electrical properties
-
[1] Liu X，Xu S R，Zhang Tao，Tao H C，Su H K，Gao Y，Xie L，Wang X H，Zhang J C，H Y 2025 Appl. Phys. Lett. 126 202103
[2] Xu S R, Wang X H, Lu H, Liu X, Yun B X, Zhang Y C, Zhang T, Zhang J C, Hao Y 2023 Acta Phys. Sin.72 196101 （in Chinese） [徐爽, 许晟瑞, 王心颢, 卢灏, 刘旭, 贠博祥, 张雅超, 张涛, 张进成, 郝跃 2023 物理学报 72 196101]
[3] Su H K, Xu S R, Tao H C, Fan X M, Du J J, Peng R S 2021 IEEE Electron Device Lett. 10 1109
[4] Xu K, Xu S R, Tao H C, Su H K, Gao Y, Yang H, An X, Huang J, Zhang J C, Hao Y 2024 CJE 52 12 (in Chinese) [许钪，许晟瑞，陶鸿昌，苏华科，高源，杨赫，安暇，黄俊，张进成，郝跃]
[5] Su H K, Zhang T, Xu S R, Tao H C, Gao Y, Liu X, Xie L, Xiang P, Cheng K, Hao Y, Zhang J C 2024 Appl. Phys. Lett. 124, 162102
[6] Tan G H, Yan F, Chen X L, Luo W K 2018 Appl.Optics.10 1364
[7] Brendel M, Helbling M, Knigge A, Brunner F, Weyers M 2015 Electr L. 51 1598-1600
[8] Zhang Y, Wong H Y, Sun M, Joglekar S, Yu L, Braga N A 2015 IEDM 10 1109
[9] Jin W Y，Zhang Y M，Xia S Y，Zhu Q Z，Sun Y H，Yi J M，Wang J F，Xu K 2024 AIP Advances 14 095118
[10] Xu J Y，Liu X，Xie B，Hao Y L，Wen C P，Wei J 2023 IEEE Trans. Electron Device 32 41260
[11] Liao Y Q，Chen T，Wang J，Cai W T，Ando Y，Yang X，Watanabe H，Tanaka A 2022 Appl. Phys. Lett. 120 122109
[12] Yoshizumi Y, Hashimoto S, Tanabe T, Kiyama M 2007 J. Cryst. Growth 298 8758
[13] Ban K, Yamamoto J, Takeda K, Ide K, Iwaya M, Takeuchi T, Kamiyama S, Akasaki I, Amano H 2011 Appl. Phys. Express 4 052101
[14] Lu H，Xu S R，Huang Y，Chen X，Xu S，Liu X，Wang X H，Gao Y，Zhang Y C，Duan X L，Zhang J C，H Y 2024 J.Inorg.Mater.202 30490
[15] Lu X, Liu C, Jiang H X, Zou X B, Zhang A P, Lau K M 2016 Appl. Phys. Express 9 031001
[16] Li Q B, Liu G X, Wang S Z, Liu L, Yu J X, Wang G D, Cui P, Zhang S Y, Xu X G, Zhang L 2025 Surf. Interfaces 56 105554
[17] Liu W S, Wu S H, Balaji G, Huang L C, Chi C K, Hu K J, Kuo H C 2024 Appl Phys A 130 801
[18] Wu P, Zhang T, Zhang J C, H Y, 2022 Acta Phys. Sin 71 158503 (in Chinese) [武鹏，张涛，张进成，郝跃 2022 物理学报 71 158503]
[19] Cao Y, Chu R, Li R, Chen M, Chang R, Hughes B 2016 Appl. Phys. Lett 108 062103
[20] Chen J B, Bian Z K, Liu Z H, Ning J, Duan X L, Zhao S L, Wang H Y, Tang Q, Wu Y H, Song Y Q, Zhang J C, Hao Y Semicond. Sci. Techno 34 115019
[21] Lambert D. J. H, Zhu T G, Shelton. B. S, Wong M M, Chowdhury U, Dupuis R. D 2000 Appl. Phys. Lett. 77, 2918–2920
[22] Witte W, Fahle D, Koch H, Heuken M, Kalisch H, Vescan A 2012 Semicond. Sci. Technol. 27 085015
[23] Zhang Y H, Sun M, Piedra D, Azize M, Zhang X, Fujishima T 2014 IEEE Trans. Electron Device 10 1109
[24] Bian Z K, Zhou H, Xu S R, Zhang T, Dang K, Chen J B, Zhang J C, Hao Y 2019 Superlattice Microst 125 295-301
[25] Tokuda H, Watanabe F, Syahiman A, Kuzuhara M, Fujiwara T 2011 IEEE MTT-S 10 1109
[26] Li L, Kishi A, Liu Q, Itai Y, Fujihara R, Ohno Y 2014 IEEE J. Electron Devices Soc. 6 168-173
[27] Sang L W, Ren B, Sumiya M, Liao M, Koide Y 2017 Appl. Phys. Lett. 111, 122102
[28] Bumho K, Daeyoung M, Kisu J, Sewoung Oh, Young Kuk Lee, Yongjo Park, Yasushi Nanishi, Euijoon Yoon Appl. Phys. Lett. 104, 102101
[29] Wang J, You H F,Guo H,Xue J J,Yang G F,Chen D J,Liu B,Lu H,Zhang r,Zheng Y D Appl. Phys. Lett. 116, 062104
Metrics
- Abstract views: 63
- PDF Downloads: 0
- Cited By: 0
下载:
