Enhanced performance of In₂O₃ nanowire field effect transistors with controllable surface functionalization of Ag nanoparticles

Abstract

Indium oxide (In 2 O 3 ) nanowire field effect transistors (FETs) have great potential in electronic and sensor applications owing to their suitable band width and high electron mobility. However, the In 2 O 3 nanowire FETs reported previously were operated in a depletion-mode, not suitable to the integrated circuits result of the high-power consumption. Therefore, tuning the electrical properties of In 2 O 3 nanowire FETs into enhancement-mode is critical for the successful application in the fields of high-performance electronics, optoelectronics and detectors. In the work, a simple but effective strategy was carried out by preparing Ag nanoparticle functionalized In 2 O 3 NWs to regulate the threshold voltage (V th ) of In 2 O 3 NW FETs, successfully achieving enhanced-mode devices. The threshold voltage can be regulated from −6.9 V to +7 V by controlling Ag density via deposition time. In addition, the devices exhibited high performance: huge I on /I off ratio > 10 8 , large maximum saturation current ≈ 800 mA and excellent carrier mobility ≈ 129 cm 2 V•s −1 . The enhanced performance is attributed to the surface passivation by Ag nanoparticles to reduce the density of traps and the charge transfer between traps and the nanowires to regulate the V th . The result indicates the application of metal nanoparticles significantly improve oxide NW for low-power FETs.

Low-Temperature As-Doped In2O3 Nanowires for Room Temperature NO2 Gas Sensing

“…In order to further explain this phenomenon, we provide two sensing mechanisms corresponding to the In 2 O 3 NWs of two diameters in Figure (b,c). Apparently, the thinner one produces more free electrons from the donor level, while the thicker one produces less free electrons. − In addition, as displayed in Figure (c), the Debye length is related to the thickness of the electron depletion layer of the In 2 O 3 NW. When in the air, oxygen will plunder electrons from the In 2 O 3 NW to form chemisorbed oxygen, forming a depletion layer.…”

Synthesis and Characterization of Indium Tin Oxide Nanowires with Surface Modification of Silver Nanoparticles by Electrochemical Method

“…Based on the results, the resistivity increased with the increasing surface modification of Ag. Since the heterojunction was formed between Ag and ITO NW, the electrons on the ITO conduction band were captured by Ag and the energy band near the surface was more curved, resulting in a larger electron depletion layer [ 37 ]. In view of the space of the electron conduction channel, when electrons are transferred, a larger energy barrier is encountered; thus, the resistivity is higher than compared to pure ITO NW.…”