Abstract
GaN-based enhancement-mode high-electron-mobility transistors (HEMTs) with a 25-nm-thick undoped GaN (u-GaN) cap underneath the gate metallization on ultrathin-barrier (UTB) AlGaN (<6 nm)/GaN heterostructures have been demonstrated. The presence of a thick u-GaN cap contributes to the increased depletion of the two-dimensional electron gas (2DEG) beneath the gate by polarization effects, resulting in an improvement of the threshold voltage (Vth) and a suppression of the off-state gate leakage (Ioff). The UTB HEMTs with a thick u-GaN cap exhibit normally-off operation with a Vth of 0.5 V, a maximum on-current of 232.1 mA/mm, an Ioff of 10−6 mA/mm, and a gate voltage swing of 7 V at a drain bias of 10 V. Thanks to the p-doping-free GaN cap, the device demonstrates excellent Vth stability under positive gate bias, which positions it as a promising candidate for future low-voltage GaN power applications.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Data Availability
The datasets generated and analyzed during the current study are available from the corresponding author on reasonable request.
References
B.J. Baliga, Gallium nitride devices for power electronic applications. Semicond. Sci. Tech. 28(7), 074011 (2013).
M. Ishida, T. Ueda, T. Tanaka, and D. Ueda, GaN on Si technologies for power switching devices. IEEE Trans. Electron Devices 60(10), 3053 (2013).
K.J. Chen, O. Häberlen, A. Lidow, C. Tsai, T. Ueda, Y. Uemoto, and Y. Wu, GaN-on-Si power technology: devices and applications. IEEE Trans. Electron Devices 64(3), 779 (2017).
M. Kuzuhara and H. Tokuda, Low-loss and high-voltage III-nitride transistors for power switching applications. IEEE Trans. Electron Devices 62(2), 405 (2015).
Y. Uemoto, M. Hikita, H. Ueno, H. Matsuo, H. Ishida, M. Yanagihara, T. Ueda, T. Tanaka, and D. Ueda, Gate injection transistor (GIT): a normally-off AlGaN/GaN power transistor using conductivity modulation. IEEE Trans. Electron Devices 54(12), 3393 (2007).
Q. Zhou, A. Zhang, B. Chen, Y. Jin, Y. Shi, Z. Wang, W. Chen, and B. Zhang, 7.6 V threshold voltage high-performance normally-off Al2O3/GaN MOSFET achieved by interface charge engineering. IEEE Electron Device Lett. 37(2), 165 (2016).
T. Oka and T. Nozawa, AlGaN/GaN recessed MIS-gate HFET with high-threshold-voltage normally-off operation for power electronics applications. IEEE Electron Device Lett. 29(7), 668 (2008).
J. He, W. Cheng, Q. Wang, K. Cheng, H. Yu, and Y. Chai, Recent advances in GaN-based power HEMT devices. Adv. Electron. Mater. 7(4), 2001045 (2021).
O. Hilt, A. Knauer, F. Brunner, E. Bahat-Treidel, and J. Würfl, Normally-off AlGaN/GaN HFET with p-type GaN Gate and AlGaN buffer, in 2010 22nd International Symposium on Power Semiconductor Devices & IC’s (ISPSD) (IEEE, 2010), p. 347
Y. Zhong, S. Su, X. Chen, Y. Zhou, H. Gao, X. Zhan, X. Guo, S. Zhang, and Q. Sun, Gate reliability and its degradation mechanism in the gate. IEEE J. Emerg. Sel. Top. Power Electron. 9(3), 3715 (2021).
X. Dai, Z. Ji, Q. Jiang, S. Huang, J. Fan, C. Feng, H. Jin, X. Wang, and X. Liu, Suppression of reverse leakage in enhancement-mode GaN high-electron-mobility transistor by extended PGaN technology. Phys. Status Solidi (a) 220(16), 2200692 (2023).
Z. Xu, J. Wang, J. Liu, C. Jin, Y. Cai, Z. Yang, M. Wang, M. Yu, B. Xie, W. Wu, X. Ma, J. Zhang, and Y. Hao, Demonstration of normally-off recess-gated AlGaN/GaN MOSFET using GaN cap layer as recess mask. IEEE Electron Device Lett. 35(12), 1197 (2014).
J. Wei, S. Liu, B. Li, X. Tang, Y. Lu, C. Liu, M. Hua, Z. Zhang, G. Tang, and K. J. Chen, Enhancement-mode GaN double-channel MOS-HEMT with low on-resistance and robust gate recess, in 2015 IEEE International Electron Devices Meeting (IEDM) (IEEE, 2015), p. 9.4.1
Y. Shi, S. Huang, Q. Bao, X. Wang, K. Wei, H. Jiang, J. Li, C. Zhao, S. Li, Y. Zhou, H. Gao, Q. Sun, H. Yang, J. Zhang, W. Chen, Q. Zhou, B. Zhang, and X. Liu, Normally off GaN-on-Si MIS-HEMTs fabricated with LPCVD-SiNx passivation and high-temperature gate recess. IEEE Trans. Electron Devices 63(2), 614 (2016).
K. J. Chen, L. Yuan, M. Wang, H. Chen, S. Huang, Q. Zhou, C. Zhou, B. Li, and J. Wan, Physics of fluorine plasma ion implantation for GaN normally-off HEMT technology, in 2011 International Electron Devices Meeting (IEDM) (IEEE, 2011), p 19.4.1
C. Liu, S. Yang, Z. Tang, H. Wang, Q. Jiang, and K.J. Chen, Thermally stable enhancement-mode GaN metal-isolator-semiconductor high-electron-mobility transistor with partially recessed fluorine-implanted barrier. IEEE Electron Device Lett. 36(4), 318 (2015).
S. Huang, X. Liu, X. Wang, X. Kang, J. Zhang, Q. Bao, K. Wei, Y. Zheng, C. Zhao, H. Gao, Q. Sun, Z. Zhang, and K.J. Chen, High uniformity normally-off GaN MIS-HEMTs fabricated on ultra-thin-barrier AlGaN/GaN heterostructure. IEEE Electron Device Lett. 37(12), 1617 (2016).
S. Huang, X. Liu, X. Wang, X. Kang, J. Zhang, J. Fan, J. Shi, K. Wei, Y. Zheng, H. Gao, Q. Sun, M. Wang, B. Shen, and K.J. Chen, Ultrathin-barrier AlGaN/GaN heterostructure: a recess-free technology for manufacturing high-performance GaN-on-Si power devices. IEEE Trans. Electron Devices 65(1), 207 (2018).
F. Benkhelifa, S. Müller, V.M. Polyakov, and O. Ambacher, Normally-off AlGaN/GaN/AlGaN double heterostructure FETs with a thick undoped GaN gate layer. IEEE Electron Device Lett. 36(9), 905 (2015).
C. Zhang and R. Yao, An enhancement-mode AlInN/GaN HEMTs combining intrinsic GaN cap layer and AlGaN back barrier layer. Solid State Commun. 336, 115150 (2023).
M. Grundman, BandEng Poisson-Schrödinger Solver Software. http://my.ece.ucsb.edu/mggrundman/bandeng (2004).
R. Zhao, S. Huang, X. Wang, Y. Li, J. Shi, Y. Zhang, J. Fan, H. Yin, X. Chen, K. Wei, S. Wu, X. Yang, B. Shen, and X. Liu, Interface charge engineering in down-scaled AlGaN (<6 nm)/GaN heterostructure for fabrication of GaN-based power HEMTs and MIS-HEMTs. Appl. Phys. Lett. 116(10), 103502 (2020).
Z. Tang, S. Huang, Q. Jiang, S. Liu, C. Liu, and K.J. Chen, High-voltage (600-V) low-leakage low-current-collapse AlGaN/GaN HEMTs with AlN/SiNx passivation. IEEE Electron Device Lett. 34(3), 366 (2013).
M. Hua, Y. Lu, S. Liu, C. Liu, K. Fu, Y. Cai, B. Zhang, and K.J. Chen, Compatibility of AlN/SiNx passivation with LPCVD-SiNx gate dielectric in GaN-based MIS-HEMT. IEEE Electron Device Lett. 37(3), 265 (2016).
S. Yang, Z. Tang, M. Hua, Z. Zhang, J. Wei, Y. Lu, and K.J. Chen, Investigation of SiNx and AlN passivation for AlGaN/GaN high-electron-mobility transistors: role of interface traps and polarization charges. IEEE J. Electron Devices Soc. 8, 358 (2020).
X. Li, B. Bakeroot, Z. Wu, N. Amirifar, S. You, N. Posthuma, M. Zhao, H. Liang, G. Groeseneken, and S. Decoutere, Observation of dynamic VTH of p-GaN gate HEMTs by fast sweeping characterization. IEEE Electron Device Lett. 41(4), 577 (2020).
J. He, G. Tang, and K.J. Chen, VTH instability of p-GaN gate HEMTs under static and dynamic gate stress. IEEE Electron Device Lett. 39(10), 1576 (2018).
C. Feng, Q. Jiang, S. Huang, X. Wang, and X. Liu, Gate-bias-accelerated VTH recovery on Schottky-type p-GaN gate AlGaN/GaN HEMTs. IEEE Trans. Electron Devices 70(9), 4591 (2023).
C.H. Chen, S.M. Baier, D.K. Arch, and M.S. Shur, A new and simple model for GaAs heterojunction FET gate characteristics. IEEE Trans. Electron Devices 35(5), 570 (1988).
Funding
This study was funded in part by the National Key Research and Development Program of China under grant 2022YFB3604400; in part by the Youth Innovation Promotion Association of Chinese Academy Sciences (CAS); in part by the CAS-Croucher Funding Scheme under grant CAS22801; in part by the National Natural Science Foundation of China under grants 62334012, 62074161, 62004213, U20A20208, and 62304252; in part by the Beijing Municipal Science and Technology Commission project under grants Z201100008420009 and Z211100007921018; in part by the University of CAS; and in part by IMECAS-HKUST-Joint Laboratory of Microelectronics.
Author information
Authors and Affiliations
Contributions
All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Yuhao Wang, Sen Huang, Qimeng Jiang, Xinhua Wang, Fuqiang Guo, Chao Feng, Jie Fan, Haibo Yin, Xinguo Gao, Ke Wei, Yingkui Zheng, and Xinyu Liu. The first draft of the manuscript was written by Yuhao Wang, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Corresponding authors
Ethics declarations
Conflict of interest
The authors declare that they have no relevant financial or non-financial interests to disclose.
Ethical Approval
This research does not involve human participants or animals.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Wang, Y., Huang, S., Jiang, Q. et al. Gate Leakage Suppression and Threshold Voltage Stability Improvement in GaN-Based Enhancement-Mode HEMTs on Ultrathin-Barrier AlGaN/GaN Heterostructures with a p-Doping-Free GaN Cap. J. Electron. Mater. (2024). https://doi.org/10.1007/s11664-024-11156-z
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11664-024-11156-z