Optical and Electronic Properties of SnO₂Thin Films Fabricated Using the SILAR Method

Abstract

Tin oxide thin films were fabricated on glass substrates by the successive ionic layer adsorption and reaction (SILAR) method at room temperature and ambient pressure. Before measuring their properties, all samples were annealed at 500 o C for 2 h in air. Film thickness increased with the number of cycles; X-ray diffraction patterns for the annealed SnO 2 thin films indicated a SnO 2 single phase. Thickness of the SnO 2 films increased from 12 to 50 nm as the number of cycles increased from 20 to 60. Although the optical transmittance decreased with thickness, 50 nm SnO 2 thin films exhibited a high value of more than 85%. Regarding electronic properties, sheet resistance of the films decreased as thickness increased; however, the measured resistivity of the thin film was nearly constant with thickness (3×10 -4 ohm/cm). From Hall measurements, the 50 nm thickness SnO 2 thin film had the highest mobility of the samples (8.6 cm 2 /(V·s)). In conclusion, optical and electronic properties of SnO 2 thin films could be controlled by adjusting the number of SILAR cycles.

Influence of the Curing and Annealing Temperatures on the Properties of Solution Processed Tin Oxide Thin Films

“…Spray pyrolysis has been shown to provide high Hall mobilities (over 10 cm 2 /Vs) with a preferred (211) orientation [32,35]. Our results are similar to the SnO 2 fabricated by the SILAR method [31]. We note nonetheless that our films are less than 50 nm, (compared to the >100 nm layers used by spray pyrolysis) and with thicker layers, the electrical conductivity may increase [28].…”

“…Hydrophilic porous SnO 2 :H 2 O thin films deposited by the sequential ionic layer adsorption and reaction (SILAR) method demonstrated a high roughness (over 200 nm) with crystals of ~15 nm [30] and a high resistivity (10 7 Ωcm at room temperature). On the other hand, it is possible to obtain films with mobility of 8.6 cm 2 /Vs after annealing at 500 • C from SnCl 2 •H 2 O precursors [31].…”

The effect of precursor concentration and post-deposition annealing on the optical and micro-structural properties of SILAR deposited SnO2 films

“…Tin oxide (SnO 2 ) is one of such earth abundant and nontoxic IV-VI material known for its transparency in visible region and a wide bandgap (3.5 to 4.0 eV) [1]. Due to its high absorption co-efficient in UV region and n-type conductivity, SnO 2 has many potential applications such as gas sensors [2], window layers in solar cells, photodetectors [3][4][5] etc The SnO 2 nano materials including thin films have been prepared by several physical and chemical routes such as chemical bath deposition [6], dip coating [7], sol-gel [8], thermal evaporation [9], Spray pyrolysis [10] pulsed laser deposition (PLD) [11], SILAR [12][13][14] etc Among these techniques, SILAR has proved to be a simple and cost-effective route for the synthesis of good quality SnO 2 films as it does not require complex setups and vacuum environment [15]. Several efforts have been made in the past to synthesize SnO 2 using SILAR and other techniques.…”