Nano Research

, Volume 11, Issue 11, pp 5935–5945 | Cite as

Towards high-mobility In2xGa2–2xO3 nanowire field-effect transistors

  • Ziyao Zhou
  • Changyong Lan
  • SenPo Yip
  • Renjie Wei
  • Dapan Li
  • Lei Shu
  • Johnny C. Ho
Research Article


Recently, owing to the excellent electrical and optical properties, n-type In2O3 nanowires (NWs) have attracted tremendous attention for application in memory devices, solar cells, and ultra-violet photodetectors. However, the relatively low electron mobility of In2O3 NWs grown by chemical vapor deposition (CVD) has limited their further utilization. In this study, utilizing in-situ Ga alloying, highly crystalline, uniform, and thin In2xGa2−2xO3 NWs with diameters down to 30 nm were successfully prepared via ambient-pressure CVD. Introducing an optimal amount of Ga (10 at.%) into the In2O3 lattice was found to effectively enhance the crystal quality and reduce the number of oxygen vacancies in the NWs. A further increase in the Ga concentration adversely induced the formation of a resistive β-Ga2O3 phase, thereby deteriorating the electrical properties of the NWs. Importantly, when configured into global back-gated NW field-effect transistors, the optimized In1.8Ga0.2O3 NWs exhibit significantly enhanced electron mobility reaching up to 750 cm2·V–1·s–1 as compared with that of the pure In2O3 NW, which can be attributed to the reduction in the number of oxygen vacancies and ionized impurity scattering centers. Highly ordered NW parallel arrayed devices were also fabricated to demonstrate the versatility and potency of these NWs for next-generation, large-scale, and high-performance nanoelectronics, sensors, etc.


In2O3 In2xGa2−2xO3 nanowire chemical vapor deposition mobility oxygen vacancy 


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We acknowledge the General Research Fund (No. CityU 11275916) and the Theme-based Research Scheme (No. T42-103/16-N) of the Research Grants Council of Hong Kong SAR, China, the National Natural Science Foundation of China (Nos. 51672229 and 61605024), the Science Technology and Innovation Committee of Shenzhen Municipality (No. JCYJ20160229165240684) and a grant from the Shenzhen Research Institute, City University of Hong Kong.

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Towards high-mobility In2xGa2–2xO3 nanowire field-effect transistors


  1. [1]
    Liu, Q. Z.; Liu, Y. H.; Wu, F. Q.; Cao, X.; Li, Z.; Alharbi, M.; Abbas, A. N.; Amer, M. R.; Zhou, C. W. Highly sensitive and wearable In2O3 nanoribbon transistor biosensors with integrated on-chip gate for glucose monitoring in body fluids. ACS Nano 2018, 12, 1170–1178.CrossRefGoogle Scholar
  2. [2]
    Meng, M.; Wu, X. L.; Ji, X. L.; Gan, Z. X.; Liu, L. Z.; Shen, J. C.; Chu, P. K. Ultrahigh quantum efficiency photodetector and ultrafast reversible surface wettability transition of square In2O3 nanowires. Nano Res. 2017, 10, 2772–2781.CrossRefGoogle Scholar
  3. [3]
    Macco, B.; Knoops, H. C. M.; Kessels, W. M. M. Electron scattering and doping mechanisms in solid-phase-crystallized In2O3:H prepared by atomic layer deposition. ACS Appl. Mater. Interfaces 2015, 7, 16723–16729.CrossRefGoogle Scholar
  4. [4]
    Park, S.; Kim, S.; Sun, G.-J.; Lee, C. Synthesis, structure, and ethanol gas sensing properties of In2O3 nanorods decorated with Bi2O3 nanoparticles. ACS Appl. Mater. Interfaces 2015, 7, 8138–8146.CrossRefGoogle Scholar
  5. [5]
    Liu, A.; Liu, G. X.; Zhu, H. H.; Xu, F.; Fortunato, E.; Martins, R.; Shan, F. K. Fully solution-processed low-voltage aqueous In2O3 thin-film transistors using an ultrathin ZrOx dielectric. ACS Appl. Mater. Interfaces 2014, 6, 17364–17369.CrossRefGoogle Scholar
  6. [6]
    Khim, D.; Lin, Y.-H.; Nam, S.; Faber, H.; Tetzner, K.; Li, R. P.; Zhang, Q.; Li, J.; Zhang, X. X.; Anthopoulos, T. D. Modulation-doped In2O3/ZnO heterojunction transistors processed from solution. Adv. Mater. 2017, 29, 1605837.CrossRefGoogle Scholar
  7. [7]
    Leppäniemi, J.; Huttunen, O.-H.; Majumdar, H.; Alastalo, A. Flexography-printed In2O3 semiconductor layers for high-mobility thin-film transistors on flexible plastic substrate. Adv. Mater. 2015, 27, 7168–7175.CrossRefGoogle Scholar
  8. [8]
    Kim, J.; Rim, Y. S.; Chen, H. J.; Cao, H. H.; Nakatsuka, N.; Hinton, H. L.; Zhao, C. Z.; Andrews, A. M.; Yang, Y.; Weiss, P. S. Fabrication of high-performance ultrathin In2O3 film field-effect transistors and biosensors using chemical lift-off lithography. ACS Nano 2015, 9, 4572–4582.CrossRefGoogle Scholar
  9. [9]
    Hou, J. G.; Cao, S. Y.; Sun, Y. Q.; Wu, Y. Z.; Liang, F.; Lin, Z. S.; Sun, L. C. Atomically thin mesoporous In2O3–x/In2S3 lateral heterostructures enabling robust broadband-light photo-electrochemical water splitting. Adv. Energy Mater. 2018, 8, 1701114.CrossRefGoogle Scholar
  10. [10]
    Ju, S.; Facchetti, A.; Xuan, Y.; Liu, J.; Ishikawa, F.; Ye, P. D.; Zhou, C. W.; Marks, T. J.; Janes, D. B. Fabrication of fully transparent nanowire transistors for transparent and flexible electronics. Nat. Nanotechnol. 2007, 2, 378–384.CrossRefGoogle Scholar
  11. [11]
    Li, C.; Zhang, D.; Han, S.; Liu, X.; Tang, T.; Zhou, C. Diameter-controlled growth of single-crystalline In2O3 nanowires and their electronic properties. Adv. Mater. 2003, 15, 143–146.CrossRefGoogle Scholar
  12. [12]
    Zou, X. M.; Liu, X. Q.; Wang, C. L.; Jiang, Y.; Wang, Y.; Xiao, X. H.; Ho, J. C.; Li, J. C.; Jiang, C. Z.; Xiong, Q. H. et al. Controllable electrical properties of metal-doped In2O3 nanowires for high-performance enhancement-mode transistors. ACS Nano 2013, 7, 804–810.CrossRefGoogle Scholar
  13. [13]
    Shen, G. Z.; Xu, J.; Wang, X. F.; Huang, H. T.; Chen, D. Growth of directly transferable In2O3 nanowire mats for transparent thin-film transistor applications. Adv. Mater. 2011, 23, 771–775.CrossRefGoogle Scholar
  14. [14]
    Lei, B.; Li, C.; Zhang, D.; Tang, T.; Zhou, C. Tuning electronic properties of In2O3 nanowires by doping control. Appl. Phys. A 2004, 79, 439–442.CrossRefGoogle Scholar
  15. [15]
    Peng, X. S.; Wang, Y. W.; Zhang, J.; Wang, X. F.; Zhao, L. X.; Meng, G. W.; Zhang, L. D. Large-scale synthesis of In2O3 nanowires. Appl. Phys. A 2002, 74, 437–439.CrossRefGoogle Scholar
  16. [16]
    Lao, J.; Huang, J.; Wang, D.; Ren, Z. Self-assembled In2O3 nanocrystal chains and nanowire networks. Adv. Mater. 2004, 16, 65–69.CrossRefGoogle Scholar
  17. [17]
    Yan, Y. G.; Zhang, Y.; Zeng, H. B.; Zhang, J. X.; Cao, X. L.; Zhang, L. D. Tunable synthesis of In2O3 nanowires, nanoarrows and nanorods. Nanotechnology 2007, 18, 175601.CrossRefGoogle Scholar
  18. [18]
    Kam, K. C.; Deepak, F. L.; Cheetham, A. K.; Rao, C. N. R. In2O3 nanowires, nanobouquets and nanotrees. Chem. Phys. Lett. 2004, 397, 329–334.CrossRefGoogle Scholar
  19. [19]
    Han, N.; Yang, Z. X.; Wang, F. Y.; Yip, S.; Dong, G. F.; Liang, X. G.; Hung, T.; Chen, Y. F.; Ho, J. C. Modulating the morphology and electrical properties of GaAs nanowires via catalyst stabilization by oxygen. ACS Appl. Mater. Interfaces 2015, 7, 5591–5597.CrossRefGoogle Scholar
  20. [20]
    Zhang, D. H.; Ma, H. L. Scattering mechanisms of charge carriers in transparent conducting oxide films. Appl. Phys. A 1996, 62, 487–492.CrossRefGoogle Scholar
  21. [21]
    Yang, Z.-X.; Yip, S.; Li, D. P.; Han, N.; Dong, G. F.; Liang, X. G.; Shu, L.; Hung, T. F.; Mo, X. L.; Ho, J. C. Approaching the hole mobility limit of GaSb nanowires. ACS Nano 2015, 9, 9268–9275.CrossRefGoogle Scholar
  22. [22]
    Shen, Y. D.; Chen, R. J.; Yu, X. C.; Wang, Q. J.; Jungjohann, K. L.; Dayeh, S. A.; Wu, T. Gibbs–Thomson effect in planar nanowires: Orientation and doping modulated growth. Nano Lett. 2016, 16, 4158–4165.CrossRefGoogle Scholar
  23. [23]
    Li, W. Q.; Liao, L.; Xiao, X. H.; Zhao, X. Y.; Dai, Z. G.; Guo, S. S.; Wu, W.; Shi, Y.; Xu, J. X.; Ren, F. et al. Modulating the threshold voltage of oxide nanowire field-effect transistors by a Ga+ ion beam. Nano Res. 2014, 7, 1691–1698.CrossRefGoogle Scholar
  24. [24]
    Nomura, K.; Ohta, H.; Takagi, A.; Kamiya, T.; Hirano, M.; Hosono, H. Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors. Nature 2004, 432, 488–492.CrossRefGoogle Scholar
  25. [25]
    Yuan, G. D.; Zhang, W. J.; Jie, J. S.; Fan, X.; Tang, J. X.; Shafiq, I.; Ye, Z. Z.; Lee, C. S.; Lee, S. T. Tunable n-type conductivity and transport properties of Ga-doped ZnO nanowire arrays. Adv. Mater. 2008, 20, 168–173.CrossRefGoogle Scholar
  26. [26]
    Park, W. J.; Shin, H. S.; Ahn, B. D.; Kim, G. H.; Lee, S. M.; Kim, K. H.; Kim, H. J. Investigation on doping dependency of solution-processed Ga-doped ZnO thin film transistor. Appl. Phys. Lett. 2008, 93, 083508.CrossRefGoogle Scholar
  27. [27]
    Kamiya, T.; Nomura, K.; Hosono, H. Origins of high mobility and low operation voltage of amorphous oxide TFTs: Electronic structure, electron transport, defects and doping. J. Disp. Technol. 2009, 5, 468–483.CrossRefGoogle Scholar
  28. [28]
    Jeong, S.; Ha, Y. G.; Moon, J.; Facchetti, A.; Marks, T. J. Role of gallium doping in dramatically lowering amorphousoxide processing temperatures for solution-derived indium zinc oxide thin-film transistors. Adv. Mater. 2010, 22, 1346–1350.CrossRefGoogle Scholar
  29. [29]
    Kim, G. H.; Jeong, W. H.; Kim, H. J. Electrical characteristics of solution-processed InGaZnO thin film transistors depending on Ga concentration. Phys. Status Solidi (a) 2010, 207, 1677–1679.CrossRefGoogle Scholar
  30. [30]
    Noh, H.-K.; Chang, K. J.; Ryu, B.; Lee, W.-J. Electronic structure of oxygen-vacancy defects in amorphous In-Ga-Zn-O semiconductors. Phys. Rev. B 2011, 84, 115205.CrossRefGoogle Scholar
  31. [31]
    Yao, J. K.; Xu, N. S.; Deng, S. Z.; Chen, J.; She, J. C.; Shieh, H.-P. D.; Liu, P.-T.; Huang, Y.-P. Electrical and photosensitive characteristics of a-IGZO TFTs related to oxygen vacancy. IEEE. Trans. Electron Dev. 2011, 58, 1121–1126.CrossRefGoogle Scholar
  32. [32]
    Zan, H. W.; Yeh, C. C.; Meng, H. F.; Tsai, C. C.; Chen, L. H. Achieving high field-effect mobility in amorphous indiumgallium- zinc oxide by capping a strong reduction layer. Adv. Mater. 2012, 24, 3509–3514.CrossRefGoogle Scholar
  33. [33]
    Johnson, M. C.; Aloni, S.; McCready, D. E.; Bourret- Courchesne, E. D. Controlled vapor–liquid–solid growth of indium, gallium, and tin oxide nanowires via chemical vapor transport. Cryst. Growth Des. 2006, 6, 1936–1941.CrossRefGoogle Scholar
  34. [34]
    Vomiero, A.; Ferroni, M.; Comini, E.; Faglia, G.; Sberveglieri, G. Insight into the formation mechanism of one-dimensional indium oxide wires. Cryst. Growth Des. 2010, 10, 140–145.CrossRefGoogle Scholar
  35. [35]
    Schmidt, V.; Senz, S.; Gösele, U. Diameter dependence of the growth velocity of silicon nanowires synthesized via the vapor-liquid-solid mechanism. Phys. Rev. B 2007, 75, 045335.CrossRefGoogle Scholar
  36. [36]
    Fröberg, L. E.; Seifert, W.; Johansson, J. Diameter-dependent growth rate of InAs nanowires. Phys. Rev. B 2007, 76, 153401.CrossRefGoogle Scholar
  37. [37]
    Gao, T.; Wang, T. H. Catalytic growth of In2O3 nanobelts by vapor transport. J. Cryst. Growth 2006, 290, 660–664.CrossRefGoogle Scholar
  38. [38]
    Yang, Z.-X.; Wang, F. Y.; Han, N.; Lin, H.; Cheung, H.-Y.; Fang, M.; Yip, S.; Hung, T.; Wong, C.-Y.; Ho, J. C. Crystalline GaSb nanowires synthesized on amorphous substrates: From the formation mechanism to p-channel transistor applications. ACS Appl. Mater. Interfaces 2013, 5, 10946–10952.CrossRefGoogle Scholar
  39. [39]
    Yang, Z.-X.; Han, N.; Fang, M.; Lin, H.; Cheung, H.-Y.; Yip, S.; Wang, E.-J.; Hung, T.; Wong, C.-Y.; Ho, J. C. Surfactant-assisted chemical vapour deposition of highperformance small-diameter GaSb nanowires. Nat. Commun. 2014, 5, 5249.CrossRefGoogle Scholar
  40. [40]
    Rao, C. N. R.; Kulkarni, G. U.; Thomas, P. J.; Edwards, P. P. Size-dependent chemistry: Properties of nanocrystals. Chem.—Eur. J. 2002, 8, 28–35.CrossRefGoogle Scholar
  41. [41]
    Volokitin, Y.; Sinzig, J.; de Jongh, L. J.; Schmid, G.; Vargaftik, M. N.; Moiseevi, I. I. Quantum-size effects in the thermodynamic properties of metallic nanoparticles. Nature 1996, 384, 621–623.CrossRefGoogle Scholar
  42. [42]
    Chen, M.; Wang, X.; Yu, Y. H.; Pei, Z. L.; Bai, X. D.; Sun, C.; Huang, R. F.; Wen, L. S. X-ray photoelectron spectroscopy and auger electron spectroscopy studies of Al-doped ZnO films. Appl. Surf. Sci. 2000, 158, 134–140.CrossRefGoogle Scholar
  43. [43]
    Kumar, V.; Swart, H. C.; Ntwaeaborwa, O. M.; Kroon, R. E.; Terblans, J. J.; Shaat, S. K. K.; Yousif, A.; Duvenhage, M. M. Origin of the red emission in zinc oxide nanophosphors. Mater. Lett. 2013, 101, 57–60.CrossRefGoogle Scholar
  44. [44]
    Yerushalmi, R.; Jacobson, Z. A.; Ho, J. C.; Fan, Z. Y.; Javey, A. Large scale, highly ordered assembly of nanowire parallel arrays by differential roll printing. Appl. Phys. Lett. 2007, 91, 203104.CrossRefGoogle Scholar
  45. [45]
    Lee, J. S.; Chang, S.; Koo, S.-M.; Lee, S. Y. High-performance a-IGZO TFT with ZrO2 gate dielectric fabricated at room temperature. IEEE Electron Dev. Lett. 2010, 31, 225–227.CrossRefGoogle Scholar
  46. [46]
    Nomura, K.; Takagi, A.; Kamiya, T.; Ohta, H.; Hirano, M.; Hosono, H. Amorphous oxide semiconductors for high-performance flexible thin-film transistors. Jpn. J. Appl. Phys. 2006, 45, 4303.CrossRefGoogle Scholar

Copyright information

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Ziyao Zhou
    • 1
    • 3
  • Changyong Lan
    • 1
    • 2
  • SenPo Yip
    • 1
    • 3
    • 4
  • Renjie Wei
    • 1
    • 3
  • Dapan Li
    • 1
    • 3
  • Lei Shu
    • 1
    • 3
    • 4
  • Johnny C. Ho
    • 1
    • 3
    • 4
  1. 1.Department of Materials Science and EngineeringCity University of Hong KongKowloon, Hong KongChina
  2. 2.School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina
  3. 3.Shenzhen Research InstituteCity University of Hong KongShenzhenChina
  4. 4.State Key Laboratory of Millimeter WavesCity University of Hong KongKowloon, Hong KongChina

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