•  
  •  
 
Nano Research

Article Title

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

Authors

Ziyao Zhou, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
Changyong Lan, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
SenPo Yip, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China State Key Laboratory of Millimeter Waves, City University of Hong Kong, Kowloon, Hong Kong 999077, China
Renjie Wei, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
Dapan Li, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China
Lei Shu, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China State Key Laboratory of Millimeter Waves, City University of Hong Kong, Kowloon, Hong Kong 999077, China
Johnny C. Ho, Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, China State Key Laboratory of Millimeter Waves, City University of Hong Kong, Kowloon, Hong Kong 999077, China

Keywords

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

Abstract

ABSTRACT 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.

Graphical Abstract

Publisher

Tsinghua University Press

Share

COinS