Tin Oxide Films Made by Physical Vapor Deposition-Thermal Oxidation and Spray Pyrolysis

Abstract

Tin oxide films have been prepared by physical vapor deposition of Sn followed by thermal oxidation and by spray pyrolysis of SnCl 4 or SnCl 4 ‚5H 4 O mixed with CH 3 OH. Phase changes and surface morphologies during the syntheses were monitored by X-ray diffraction and scanning electron microscopy. Electrical resistance and UV-visible transmittance of tin oxide films prepared by both methods were measured. The peak shapes of the Auger Sn M 4 N 45 N 45 transition of the prepared tin oxide films were compared to those of commercial SnO and SnO 2 and used to determine rough values of the oxidation state of Sn. Oxygen/tin ratios in the films were determined from analyses of scanning Auger microprobe and X-ray photoelectron spectroscopy and are all less than 2. Auger depth profiles with thermally oxidized tin oxide films on glass substrates show an overlapping region between the tin oxide film and the substrate. These films were tested as sensors for CH 2 Cl 2 in O 2 . The mixed phase (SnO‚SnO 2 ) tin oxide films prepared by temperature-programmed thermal oxidation of Sn showed better sensing behavior to CH 2 Cl 2 than single phase (SnO or SnO 2 ) films.

A study of the nano-structured aggregated tin oxides (SnO2/SnO) and their structural and photoluminescence properties by a hydrothermal method

“…For this reason, very few articles on the synthesis of SnO nanostructures have been reported [4][5][6]. When the n-type semiconductor metal oxide is mixed with the p-type semiconductor metal oxide nanostructures, it can be useful for new applications in material science [7]. The mixed phase of tin oxide (n-type-SnO 2 / p-type-SnO) nanostructures shows better sensing behavior than the single phase of SnO 2 or SnO nanostructures reported in literature [7].…”

“…Mixed Semiconducting Oxide (MSO) nanostructures (SnO/ SnO 2 , CoO/Co 3 O 4 and Cu 2 O/CuO) have been intensively studied [7][8][9]. The methods reported for obtaining MSO nanostructures include colloidal growth, hydrothermal synthesis, chemical vapor condensation, spray pyrolysis, sputtering and laser ablation in liquids and gases [7][8][9].…”

“…The methods reported for obtaining MSO nanostructures include colloidal growth, hydrothermal synthesis, chemical vapor condensation, spray pyrolysis, sputtering and laser ablation in liquids and gases [7][8][9]. In the present study, we have employed the hydrothermal method to produce mixed semiconductor oxide (SnO 2 /SnO) nanostructures.…”

Effect of Sintering Temperatures on the Synthesis of SnO2 Nanospheres

“…Tin oxide (SnO 2 ), a ntype semiconductor with a wide band gap (3.6 eV, at 300 K), is well known for its potential applications in gas sensors, dye sensitized solar cells, and transparent conducting electrodes and as a catalyst support [3,4]. Therefore, many processes have been proposed to synthesize SnO 2 nanostructures; some involve dry processes such as sputtering from tin oxide target [5] or from metallic target followed by oxidation [6] and chemical vapour deposition (CVD) [7], while others are based on wet processes, including spray pyrolysis [8] and sol-gel-related methods which have been used to prepare tin oxide coating, particles, and precipitates [9][10][11][12][13][14][15].…”

Synthesis and characterization of crystalline tin oxide nanoparticles

“…[14][15][16][17][18][19] In such an application, reducing the size of the particles, down to a few nanometers, is of interest since the sensitivity of the sensors can be greatly increased as a result of the associated increase of the active surface where oxygen adsorption/desorption can take place. 15,16,20,21 Tin oxide-based materials have been prepared by many different techniques; some involve dry processes, such as sputtering from a tin oxide target 22,23 or from a metallic target followed by oxidation, 24 laser ablation 15 and chemical vapor deposition (CVD), 25 others are based on wet processes, including spray pyrolysis, [26][27][28] decomposition/oxidation of tin(II) amides 29 and sol-gel-related methods, which have been used to prepare tin oxide coatings, particles and precipitates. 4,6,[30][31][32][33][34][35][36][37][38][39][40][41][42] Among the different possible synthetic outcomes, stable sols of crystalline tin oxide nanoparticles are of interest for the preparation of antistatic coatings, 13 conductive coatings, 4 filtration membranes 4 and gas sensors.…”