SEMICONDUCTOR DEVICES

Low ohmic contact AlN/GaN HEMTs grown by MOCVD

Guodong Gu, Shaobo Dun, Yuanjie Lü, Tingting Han, Peng Xu, Jiayun Yin and Zhihong Feng

+ Author Affiliations

 Corresponding author: Feng Zhihong, Email:blueledviet@yahoo.com.cn

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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.

Key words: AlN/GaN HEMTohmic contactSiC substrateMOCVD



[1]
Micovic M, Kurdoghlian A, Hashimoto P, et al. GaN HFET for W-band power applications. IEDM Tech Dig, 2006:1
[2]
De Jaeger J C, Delage S L, Dambrine G, et al. Noise assessment of AlGaN/GaN HEMTs on Si or SiC substrates:application to X-band low noise amplifiers. European Gallium Arsenide and Other Semiconductor Application Symposium, EGAAS, 2005:229 http://core.ac.uk/display/11068817
[3]
Dabiran A M, Wowchak A M, Osinsky A, et al. Very high channel conductivity in low-defect AlN/GaN high electron mobility transistor structures. Appl Phys Lett, 2008, 93(8):082111 doi: 10.1063/1.2970991
[4]
Xing H G, Deen D, Cao Y, et al. PMBE-grown ultra-shallow AlN/GaN HFET technology. ECS Trans, 2007, 11(5):233 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.712.3111
[5]
Cao Y, Jena D. High-mobility window for two-dimensional electron gases at ultrathin AlN/GaN heterojunctions. Appl Phys Lett, 2007, 90(18):182112 doi: 10.1063/1.2736207
[6]
Shinohara K, Regan D, Corrion A, et al. Deeply-scaled self-aligned-gate GaN DH-HEMTs with ultrahigh cut-off frequency. IEDM Tech Dig, 2011:457 http://www.mdpi.com/2079-9292/5/1/12/xml
[7]
Shinohara K, Regan D, Corrion A, et al. Self-aligned-gate GaN-HEMTs with heavily-doped n+-GaN ohmic contacts to 2DEG. IEDM Tech Dig, 2012:617 http://www-mtl.mit.edu/wpmu/ar2013/high-linearity-gan-hemts-with-nanowire-channel/
[8]
Medjdoub F, Zegaoui M, Waldhoff N, et al. Above 600 mS/mm transconductance with 2.3 A/mm drain current density AlN/GaN high-electron mobility transistors grown on silicon. Appl Phys Exp, 2011, 4(6):064106 doi: 10.1143/APEX.4.064106
[9]
Corrion A L, Shinohara K, Regan D, et al. High-speed AlN/GaN MOS-HFETs with scaled ALD Al2O3 gate insulators. IEEE Electron Device Lett, 2011, 32(8):1062 doi: 10.1109/LED.2011.2155616
[10]
Chabak K D, Walker D E, Johnson M R, et al. High-performance AlN/GaN HEMTs on sapphire substrate with an oxidized gate insulator. IEEE Electron Device Lett, 2011, 32(11):1677 http://adsabs.harvard.edu/abs/2011IEDL...32.1677C
[11]
Kim D W, Baik H K. Current conduction mechanism of Si/Ti-based ohmic contacts to n-GaN. Appl Phys Lett, 2000, 77(7):1011 doi: 10.1063/1.1289057
[12]
Lin C F, Cheng H C, Chi G C, et al. Improved contact performance of GaN film using Si diffusion. Appl Phys Lett, 2000, 76(14):1878 doi: 10.1063/1.126198
[13]
Mohammed F M, Wang L, Adesidaa I. First-layer Si metallizations for thermally stable and smooth ohmic contacts for AlGaN/GaN high electron mobility transistors. J Vac Sci Technol B, 2007, 25(2):324 doi: 10.1116/1.2437161
Fig. 1.  Schematic of the material structure of an AlN/GaN HEMT on an SiC substrate.

Fig. 2.  (a) The contact resistivity and contact resistance of Si/Ti/Al/Ni/Au as a function of annealing temperature. (b) The measured resistance versus gap spacing and the extracted contact and sheet resistances from the TLM pads. The optical micrograph of the contacts on the AlN/GaN structures is inserted in Fig. 2(b).

Fig. 3.  The (a) transfer characteristics and (b) output characteristics of an AlN/GaN HEMT with a 0.25 $\mu $m gate length.

Fig. 4.  The off-state breakdown characteristics of an AlN/GaN HEMT ($L_{\rm gd}$ $=$ 1.9 $\mu$m) (the $I_{\rm G}$$V_{\rm G}$ characteristics of an AlN/GaN HEMT is shown in the inset).

Fig. 5.  The small signal characteristics of an AlN/GaN HEMT device with a 0.25 $\mu $m gate length and a 2 $\times$ 20 $\mu$m gate width.

[1]
Micovic M, Kurdoghlian A, Hashimoto P, et al. GaN HFET for W-band power applications. IEDM Tech Dig, 2006:1
[2]
De Jaeger J C, Delage S L, Dambrine G, et al. Noise assessment of AlGaN/GaN HEMTs on Si or SiC substrates:application to X-band low noise amplifiers. European Gallium Arsenide and Other Semiconductor Application Symposium, EGAAS, 2005:229 http://core.ac.uk/display/11068817
[3]
Dabiran A M, Wowchak A M, Osinsky A, et al. Very high channel conductivity in low-defect AlN/GaN high electron mobility transistor structures. Appl Phys Lett, 2008, 93(8):082111 doi: 10.1063/1.2970991
[4]
Xing H G, Deen D, Cao Y, et al. PMBE-grown ultra-shallow AlN/GaN HFET technology. ECS Trans, 2007, 11(5):233 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.712.3111
[5]
Cao Y, Jena D. High-mobility window for two-dimensional electron gases at ultrathin AlN/GaN heterojunctions. Appl Phys Lett, 2007, 90(18):182112 doi: 10.1063/1.2736207
[6]
Shinohara K, Regan D, Corrion A, et al. Deeply-scaled self-aligned-gate GaN DH-HEMTs with ultrahigh cut-off frequency. IEDM Tech Dig, 2011:457 http://www.mdpi.com/2079-9292/5/1/12/xml
[7]
Shinohara K, Regan D, Corrion A, et al. Self-aligned-gate GaN-HEMTs with heavily-doped n+-GaN ohmic contacts to 2DEG. IEDM Tech Dig, 2012:617 http://www-mtl.mit.edu/wpmu/ar2013/high-linearity-gan-hemts-with-nanowire-channel/
[8]
Medjdoub F, Zegaoui M, Waldhoff N, et al. Above 600 mS/mm transconductance with 2.3 A/mm drain current density AlN/GaN high-electron mobility transistors grown on silicon. Appl Phys Exp, 2011, 4(6):064106 doi: 10.1143/APEX.4.064106
[9]
Corrion A L, Shinohara K, Regan D, et al. High-speed AlN/GaN MOS-HFETs with scaled ALD Al2O3 gate insulators. IEEE Electron Device Lett, 2011, 32(8):1062 doi: 10.1109/LED.2011.2155616
[10]
Chabak K D, Walker D E, Johnson M R, et al. High-performance AlN/GaN HEMTs on sapphire substrate with an oxidized gate insulator. IEEE Electron Device Lett, 2011, 32(11):1677 http://adsabs.harvard.edu/abs/2011IEDL...32.1677C
[11]
Kim D W, Baik H K. Current conduction mechanism of Si/Ti-based ohmic contacts to n-GaN. Appl Phys Lett, 2000, 77(7):1011 doi: 10.1063/1.1289057
[12]
Lin C F, Cheng H C, Chi G C, et al. Improved contact performance of GaN film using Si diffusion. Appl Phys Lett, 2000, 76(14):1878 doi: 10.1063/1.126198
[13]
Mohammed F M, Wang L, Adesidaa I. First-layer Si metallizations for thermally stable and smooth ohmic contacts for AlGaN/GaN high electron mobility transistors. J Vac Sci Technol B, 2007, 25(2):324 doi: 10.1116/1.2437161
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    Received: 29 March 2013 Revised: 23 April 2013 Online: Published: 01 November 2013

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      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 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.Export: BibTex EndNote
      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

      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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      Low ohmic contact AlN/GaN HEMTs grown by MOCVD

      doi: 10.1088/1674-4926/34/11/114004
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      • Corresponding author: Feng Zhihong, Email:blueledviet@yahoo.com.cn
      • Received Date: 2013-03-29
      • Revised Date: 2013-04-23
      • Published Date: 2013-11-01

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