• Journal of the Korean Society for Heat Treatment
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• v.30 no.2
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• pp.61-66
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• 2017

$SnO_2$ was electrodeposited on nodule-type Cu foil at varing current density and electrodeposition time. Unlike the previous research results, when the anodic current is applied, the $SnO_2$ layer was not electrodeposited and the substrate is corroded. When the cathodic current was applied, the $SnO_2$ layer could be successfully deposited. At this time, the surface microstructure of the powdery type was observed, which showed similar crystallinity to amorphous and had a very large surface area. Crystallinity increased after low-temperature heat treatment at $250^{\circ}C$ or lower. As a result of evaluating the charge/discharge performances as an anode material for lithium ion battery, it was confirmed that the capacity of the heat treated $SnO_2$ was increased more than 2 times, but it still showed a limit point showing initial low coulombic efficiency and low cyclability. However, it was confirmed that the battery performances may be enhanced through optimizing the electrodeposition process and introducing post heat treatment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.536-542
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• 2018

Tin dioxide, $SnO_2$, is a well-known n-type semiconductor that shows change in resistance in the presence of gas molecules, such as $H_2$, CO, and $CO_2$. Considerable research has been done on $SnO_2$ semiconductors for gas sensor applications due to their noble property. The nanomaterials exhibit a high surface to volume ratio, which means it has an advantage in the sensing of gas molecules. In this study, SnO nanoplatelets were grown densely on Si substrates using a thermal CVD process. The SnO nanostructures grown by the vapor transport method were post annealed to a $SnO_2$ phase by thermal CVD in an oxygen atmosphere at $830^{\circ}C$ and $1030^{\circ}C$. The pressure of the furnace chamber was maintained at 4.2 Torr. The crystallographic properties of the post-annealed SnO nanostructures were investigated by Raman spectroscopy and XRD. The change in morphology was confirmed by scanning electron microscopy. As a result, the SnO nanostructures were transformed to a $SnO_2$ phase by a post-annealing process.

• Applied Microscopy
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• v.49
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• pp.1.1-1.10
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• 2019

Joints of three-dimensional (3D) rutile-type (r) tin dioxide ($SnO_2$) nanowire networks, produced by the flame transport synthesis (FTS), are formed by coherent twin boundaries at $(101)^r$ serving for the interpenetration of the nanowires. Transmission electron microscopy (TEM) methods, i.e. high resolution and (precession) electron diffraction (PED), were utilized to collect information of the atomic interface structure along the edge-on zone axes $[010]^r$, $[111]^r$ and superposition directions $[001]^r$, $[101]^r$. A model of the twin boundary is generated by a supercell approach, serving as base for simulations of all given real and reciprocal space data as for the elaboration of three-dimensional, i.e. relrod and higher order Laue zones (HOLZ), contributions to the intensity distribution of PED patterns. Confirmed by the comparison of simulated and experimental findings, details of the structural distortion at the twin boundary can be demonstrated.

• The Korean Journal of Ceramics
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• v.5 no.2
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• pp.125-130
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• 1999

After $SnO_2$ fine powder by precipitation method, Ca as crystallization inhibitor and Pd as catalyst were added to $SnO_2$ raw material by various methods. Thick film device was fabricated on the alumina substrate by mixing ethylene glycol and such mixed powders. The sensing characteristics of the device for methane gas were investigated. The most excellent gas sensing property was shown by the thick film device fabricated by Method 3 in which Ca and Pd doped $SnO_2$ powder is prepared by mixing $SnO_2$ powder, 0.1 wt% Ca acetate and 1 wt% $PdCl_2$ in deionized water and by calcining the mixture, after $Sn(OH)_4$ is dried at $110^{\circ}C$ for 36h. The sensitivity of the sensor fabricated with $SnO_2$-0.1 wt%Ca acetate-1wt%$PdCl_2$ powder heat-treated at $700^{\circ}C$ for 1h was about 86% for 5,000 ppm methane in air at $350^{\circ}C$ of the operating temperature. Response time and recovery were also excellent.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.254-254
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• 2016

Tin dioxide (SnO2) thin film is one of the most important n-type semiconducting materials having a high transparency and chemical stability. Due to their favorable properties, it has been widely used as a base materials in the transparent conducting substrates, gas sensors, and other various electronic applications. Up to now, SnO2 thin film has been extensively studied by a various deposition techniques such as RF magnetron sputtering, sol-gel process, a solution process, pulsed laser deposition (PLD), chemical vapor deposition (CVD), and atomic layer deposition (ALD) [1-6]. Among them, ALD or plasma-enhanced ALD (PEALD) has recently been focused in diverse applications due to its inherent capability for nanotechnologies. SnO2 thin films can be prepared by ALD or PEALD using halide precursors or using various metal-organic (MO) precursors. In the literature, there are many reports on the ALD and PEALD processes for depositing SnO2 thin films using MO precursors [7-8]. However, only ALD-SnO2 processes has been reported for halide precursors and PEALD-SnO2 process has not been reported yet. Herein, therefore, we report the first PEALD process of SnO2 thin films using SnCl4 and oxygen plasma. In this work, the growth kinetics of PEALD-SnO2 as well as their physical and chemical properties were systemically investigated. Moreover, some promising applications of this process will be shown at the end of presentation.

• Journal of Sensor Science and Technology
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• v.16 no.6
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• pp.428-433
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• 2007

$SnO_{2}$-based thick film ethanol gas sensors were fabricated on alumina substrates and their ethanol gas sensing characteristics were investigated. The film sintered at $400^{\circ}C$ for 2 hrs. showed the highest sensitivity to ethanol gas and the sensitivity of the film to 1000 ppm ethanol gas in air was 97 % at an operating temperature of $250^{\circ}C$. The addition of $Fe_{2}O_{3}$ to $SnO_{2}$ enhanced the sensitivity by changing the type and number of surface acidic/basic sites.

• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.23-29
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• 2020

Electrochromic (EC) device is an element whose transmittance is changed by electrical energy. Coloring and decoloring states can be easily controlled and thus used in buildings and automobiles for energy saving. There exist several types of EC devices; EC using electrolytes, polymer dispersed liquid crystal (PDLC), and suspended particle device (SPD) using polarized molecules. However, these devices involve solutions such as electrolytes and liquid crystals, limiting their applications in high temperature environments. In this study, we have studied all-solid-state EC device based on Tin(IV) oxide (SnO₂). A coloring phase is achieved when electrons are accumulated in the ultraviolet (UV)-treated SnO₂ layer, whereas a decoloring mode is obtained when electrons are empty there. The UV treatment of SnO₂ layer brings in a number of localized states in the bandgap, which traps electrons near the conduction band. The SnO₂-based EC device shows a transmittance of 70.7% in the decoloring mode and 41% in the coloring mode at a voltage of 2.5 V. We have achieved a transmittance change as large as 29.7% at the wavelength of 550 nm. It also exhibits fast and stable driving characteristics, which have been demonstrated by the cyclic experiments of coloration and decoloration. It has also showed the memory effects induced by the insulating layer of titanium dioxide (TiO₂) and silicone (Si).

• Journal of the Korean Ceramic Society
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• v.41 no.1
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• pp.36-40
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• 2004

$SnO_2$ thin films were deposited on a $SiO_2$/Si substrate with the flow of Ar and $O_2$ of 25 sccm by RF-magnetron sputtering method. the post-annealing was conducted at $500^{\circ}C$ in atmosphere of dry air and $N_2$ were changed fairly, while those annealed in dry air resembled as-deposited films. This may be attributed to the desorption of adsorbed oxygen and the extraction of lattice oxygen during annealing. Resistivity of films annealed in $N_2$ was increased over 5 times than that of as-deposited films. It can be explained that the increment of resistivity may result from the discontinuous conduction path with change of microstructures after annealing in $N_2$.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.4
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• pp.101-106
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• 2008

The $SnO_2$ thin films doped with Pd and CNT as $NO_2$ gas sensor were prepared by spin coating and then the $NO_2$ gas response of these films were evaluated under $1ppm{\sim}5ppm\;NO_2$ concentration and operating temperature of $200^{\circ}C$. It was found that the sensor resistance was increased with $NO_2$ exposure and $NO_2$ concentration. The 3wt% Pd doped sample showed a sensitivity of 26.5 which was 10 times higher than that of pure $SnO_2$. And also the sensitivity of CNT doped sample increased with CNT content and it had 72 when 0.225 wt% of CNT was added under 5ppm $NO_2$ concentration.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.482-490
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• 1992

2,5-dimethoxy-2,5-dihydrofurfuryl alcohol was electrosynthesized from furfuryl alcohol in methanol solution by using three kinds of metal oxide anode. The electrods were prepared by the following process : Thin layer of semiconducting material such as tin(IV)oxide and antimony(III)oxide was made on the titanium base metal in an electric furnace. The titanium metal block with the layer was coated with ${\alpha}-PbO_2$, ${\beta}-PbO_2$, and $MnO_2$ in each electrolytes by anodic deposition, respectively. The lead dioxide electrodes showed better anti-corrosive property than the manganase dioxide electrode. The yield of the product was 92% which is almost the same as the one with conventional platinum electrodes.