Fig. 1.
Schematic of the material structure of an AlN/GaN HEMT on an SiC substrate.
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| Citation: |
Guodong Gu, Shaobo Dun, Yuanjie Lü, Tingting Han, Peng Xu, Jiayun Yin, Zhihong Feng. Low ohmic contact AlN/GaN HEMTs grown by MOCVD[J]. Journal of Semiconductors, 2013, 34(11): 114004. doi: 10.1088/1674-4926/34/11/114004
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G D Gu, S B Dun, Y Lü, T T Han, P Xu, J Y Yin, Z H Feng. Low ohmic contact AlN/GaN HEMTs grown by MOCVD[J]. J. Semicond., 2013, 34(11): 114004. doi: 10.1088/1674-4926/34/11/114004.
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Abstract
AlN/GaN high-electron-mobility transistors (HEMTs) on SiC substrates were fabricated by metal-organic chemical vapor deposition (MOCVD) and then characterized. An Si/Ti/Al/Ni/Au stack was used to reduce ohmic contact resistance (0.33 Ω· mm) at a low annealing temperature. The fabricated devices exhibited a maximum drain current density of 1.07 A/mm (VGS=1 V) and a maximum peak extrinsic transconductance of 340 mS/mm. The off-state breakdown voltage of the device was 64 V with a gate-drain distance of 1.9 μm. The current gain extrinsic cutoff frequency fT and the maximum oscillation frequency fmax were 36 and 80 GHz with a 0.25 μm gate length, respectively.-
Keywords:
- AlN/GaN HEMT,
- ohmic contact,
- SiC substrate,
- MOCVD
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References
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