Effect of Nb doping on the structural, morphological, optical and electrical properties of RF magnetron sputtered In₂O₃ nanostructured films

Abstract

Undoped and niobium (Nb) doped indium oxide (In2O3) thin films are prepared by radio frequency magnetron sputtering technique. The effect of Nb on the structural, morphological, optical and electrical properties of In2O3films are analyzed using techniques such as X‐ray diffraction (XRD), micro‐Raman spectroscopy, X‐ray photoelectron spectroscopy, atomic force microscopy, field emission scanning electron microscopy (FESEM), energy dispersive X‐ray spectroscopy, UV–visible spectroscopy, spectroscopic ellipsometry, photoluminescence spectroscopy and Hall effect measurements. XRD analysis reveals that the as‐deposited undoped and Nb doped films are polycrystalline in nature with cubic bixbyite structure. Raman analysis supports the presence of cubic bixbyite structure of In2O3in the films. XPS analysis shows a decrease of oxygen deficiency due to Nb and the existence of Nb as Nb4+ in the In2O3lattice. The band gap energy of the films increases with increase in Nb concentration. PL spectra reveal intense UV and visible emissions in all the films. Optical constants of the films are determined using spectroscopic ellipsometry. The thickness of films estimated using FESEM and ellipsometry are in good agreement. The carrier concentration, mobility and nature of carriers are measured using Hall measurement technique in Van der Pauw configuration at room temperature.

Nanometric Surface-Selective Regulation of Au/In2O3 Nanofibers as an Exhaled H2S Chemiresistor for Periodontitis Diagnosis

“…The In 3d 3/2 and In 3d 5/2 peaks were obtained at 451.5 and 443.97 eV in Au/ In 2 O 3 , respectively (Figure S6b), which is related to the characteristic peaks of In 3+ . 21,22 After SAM modification, the In 3d peaks all shifted to a higher energy side in some extent, indicating that the loading of SAMs changed the chemical environment around the indium atom. 23 In addition, C−Si−O peaks could be detected in the SAM-loaded Au/In 2 O 3 NF samples in contrast to the pristine Au/In 2 O 3 NF sample (Figure S6c), demonstrating the successful and firm surface modification of SAMs via Si−O−In bonds via the hydrolysis reaction (Figure S6d).…”

Effects of Doping Ratio and Thickness of Indium Tin Oxide Thin Films Prepared by Magnetron Sputtering at Room Temperature

“…The tin donor was activated by crystallization due to the increase in thickness, as indicated in Figure 7, but not due to the substrate heating or annealing treatment. For a thickness less than d c , a moderate doping ratio was required in order to obtain higher electrical conductivity, seemly owing to the formation of energetically favorable V O -In i and V O -Sn In proposed by Tang et al [17] because too high a doping ratio would lead to lower carrier concentration and a lower doping ratio to more tin substitution inactivated. Apparently, the trend of electrical resistivity was coherent with the conversion from an amorphous to a crystalline state.…”

“…However, only Yang et al reported [15] that even lower resistivity could be obtained by sputtering ITO ceramic targets with doping metallic tin via co-sputtering. For the convenience of ITO target production, tin is still the favorite doping element although other doping elements have been reported already, e.g., Ti [16], Nb [17], Si [4], and H [18]. In addition, ITO films with thin thickness, i.e., less than 50 nm are of great technological importance in many applications, such as touch panels [7], which is quite different from the thicker ITO (several hundreds of nanometers) on glass for de-icing.…”

Au Nanoparticle and CdS Quantum Dot Codecoration of In2O3 Nanosheets for Improved H2 Evolution Resulting from Efficient Light Harvesting and Charge Transfer

“…Photocatalytic water splitting hydrogen evolution converts endless solar energy to clean and environmentally friendly hydrogen fuel, thus becoming an impressive strategy in addressing the problems of both energy and environment. − In 2 O 3 , as a well-known moderate band gap semiconductor (2.8 eV), possesses appropriate energy band structure, easily regulated morphology, low toxicity, and good stability and thus has received extensive attention in many areas. − Although In 2 O 3 with different morphologies, such as In 2 O 3 nanorods, , microspheres, mesoporous films, nanowires, , and microflowers (MFs) assembled with nanosheets, − have been studied as photocatalysts, their photocatalytic performances for hydrogen evolution are still very poor because of the limited absorption of solar light and the serious recombination of charge carriers. , Therefore, it is very important to seek effective strategies to solve these two main problems simultaneously for obtaining novel In 2 O 3 -based photocatalysts with high photocatalytic efficiency.…”