AlN/GaN HEMT with Gate Insulation and Current Collapse Suppression Using Thermal ALD ZrO2
- 1 Downloads
In this letter, we report the device characteristics of AlN/GaN MIS-HEMT on silicon substrate using thermal atomic-layer-deposition (ALD) ZrO2 with various thicknesses. The thermal ALD ZrO2 thin film is deposited at 250°C, which avoids plasma enhancement during the fabrication process. From the transmission electron microscopy results, it is found that the alloy penetrates to the 2DEG region to form a carrier conductive pathway which facilitates the ohmic contact formation. The optimized 7 nm-thick ZrO2 AlN/GaN MIS-HEMT exhibits improved Ion/Ioff ratio and suppressed current collapse degradation, compared with 4 nm-thick ZrO2 AlN/GaN MIS-HEMT and Schottky gate AlN/GaN HEMT (SG-HEMT). In addition, as compared to SG-HEMT, reverse gate leakage current can be reduced by about six orders and forward gate bias extends to + 6.3 V with 7 nm-thick ZrO2 AlN/GaN MIS-HEMT.
KeywordsHEMT ALD ZrO2 passivation
Unable to display preview. Download preview PDF.
The authors would like to thank Y. P. Wang, B. Zhu S. X. Zhao, Z. Liu and Z.Y Su for the technical support on device fabrications. This work was supported in part by the National Science and Technology Major Project of China under Grant 2013ZX02308004, the Doctoral Scientific Research Start-Up Foundation of Henan Normal University under Grant 5101239170008 and in part by Key Laboratory of Optoelectronic Sensing Integrated Application of Hennan Province.
- 5.K. Shinohara, A. Corrion, D. Regan, I. Milosavljevic, D. Brown, S. Burnham, P. J. Willadsen, C. Butler, A. Schmitz, D. Wheeler, A. Fung, and M. Micovic, Tech. Dig-Int. Electron Devices Meet. 10, 672 (2010).Google Scholar
- 15.S. Taking, D. MacFarlane, and E. Wasige, I.E.E.E. Trans. Electron Devices 58, 1418 (2011).Google Scholar
- 22.L. He, F. Yang, L. Li, Z. Chen, Z. Shen, Y. Zheng, Y. Yao, Y. Ni, D. Zhou, X. Zhang, L. He, Z. Wu, B. Zhang, and Y. Liu, I.E.E.E. Trans. Electron Devices 64, 1554 (2017).Google Scholar