• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.3
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• pp.294-305
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• 1994

The influence of deposition parameter on the electrical, optical andsurface morphology of $SnO_2(:F)$ films prepared by ultrasonic spray deposition using DBDA and $SnCl_4.5H_2O$ as a source material was studied. Resistivity was decreased sharply with increasing F/Sn ratio in solution up to 0.6. Depending on the source material, $SnCl_4.5H_2O$ shows lower resistivity than DBDA. When F/Sn ratio in solution was 1, optical transmittance was higher DBDA than $SnCl_4.5H_2O$.

• Journal of Sensor Science and Technology
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• v.3 no.2
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• pp.65-73
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• 1994

TO:F($SnO_{2}:F$) thin films were prepared by RF magnetron sputtering system. The dependence of their structural, electrical, and optical properties on deposition conditions such as substrate temperature, working pressure and power was studied. The optimum conditions of TO:F thin film are $SnF_{2}$ content of 15wt.% in target, RF power of 150W, substrate temperature of $150^{\circ}C$ and working pressure of 2mmTr. The resistivity and transmittance at 550nm in visible spectrum of the TO:F film deposited at optimum condition are $9{\times}10^{-4}{\Omega}{\cdot}cm$ and above 85%, respectively. For the films deposited from the target without $SnF_{2}$ and with 15wt.% $SnF_{2}$, the optical bandgaps calculated from the transmittance curves are 3.84 and 3.9eV, respectively. X-ray diffraction patterns showed that TO and TO:F films had tetragonal rutile structure with (101), (200) direction.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1147-1149
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• 1993

ZnO/$SnO_2$:F bilayer films have been prepared by pyrosol deposition method to develop optimum transparent electrode for use in amorphous silicon solar cells. The solution for $SnO_2:F$ film was composed of $SnCl_4{\cdot}5H_2O,\;NH_4F,\;CH_3OH$ and HCl, and ZnO films have been deposited on the $SnO_2:F$ films by using the solution of $ZnO(CH_3COO){_2}{\cdot}2H_2O,\;H_2O\;and\;CH_3OH$. These films have been investigated the variation of electrical and optical properties under the hydrogen plasma exposure. The sheet resistance of the $SnO_2:F$ film was sharply increased and its transmittance was decreased with the blackish effect after plasma treatment. However, the ZnO/$SnO_2:F$ bilayer film was shown hydrogen plasma durability because the electrical and optical properties was almost unchanged more then 60 seconds exposure time.

• Journal of the Korean institute of surface engineering
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• v.32 no.2
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• pp.125-133
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• 1999

Fluorine-doped $SnO_2$ thin films were deposited on soda-lime glass substrates by reactive DC magnetron sputtering method. Crystallinity as well as electrical and optical properties of $SnO_2$ : F thin film were investigated as the variations of deposition conditions such as substrate temperature, DC Power, $O_2$ gas pressure, $SF_6$ gas pressure. $SnO_2$ : F thin film deposited with 5% $SF_6$ gas pressure showed electrical resistivities of $2.5\times10^{-3}$cm with the average optical transparency (about 80%) These electrical and optical properties were found to be related to the crystallinity of $SnO_2$ : F thin films.

• Journal of the Korean Chemical Society
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• v.41 no.4
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• pp.175-179
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• 1997

Luminescence of $Eu^{3+}$ has been studied in $Sr_{2-2x}Eu_xK_xSnO_4$ with two-dimensional $K_2NiF_4$ structure. The $^5D_o$ → $^7F_o$$Eu^{3+}$ ion represents the J=0 → J=0 transition which is forbidden by a Judd-Ofelt selection rule for electric dipole transition in 4f shell of $Eu^{3+}$ ions. However, the emission line of $^5D_o$ → $^7F_o$$Eu^{3+}$ emission spectra of Sr2-2xEuxKxSnO4$Sr_{2-2x}Eu_xK_xSnO_4$structure around $Eu^{3+}$ ions.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.187-190
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• 1990

A new technique is described for developing low-cost $SnO_2$ : F thin films as TCO (Transparent Conducting Oxide) substrate of a-Si solar cells. A novel Pyrosol equipment has been developed, and $SnO_2$ : F thin films have been deposited under the condition of varing dopant concentration, temperature and composition rate of solution. Futhermore, electrical and optical properties of thin films have been measured, and exhibit resistivity of $4.3{\times}10^{-4}{\Omega}$ cm and transmittance of 80% which is almost at the same level as those of $SnO_2$ : F thin films by CVD.

• Journal of Korean society of Dental Hygiene
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• v.1 no.1
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• pp.125-132
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• 2001

This study was carried out to investigate the effect of multi or single application of fluoride plus 0.05% NaF solution on the remineralization of dental caries lesion. The microhardness changes of enamel surface were measured after application of fluoride and precipitation of 0.05% NaF solution on 6 groups of cow's tooth on which the artificial carious lesions were formed first. Test groups were calssified into two step application with NaF, $SnF_2$ and APF under different application time conditions plus 0.05% NaF solution(group I, II, III, IV) and single application with APF plus 0.05% NaF solution (group V) and control(0.05% NaF solution only, group IV). The obtained results were as follows. 1. Regarding microhardness change of enamel surface. microhardness increments in group I(NaF for 1 minute+APF for 3 minutes+0.05% NaF solution for 1 minute), II($SnF_2$ 1 min+APF 3 min+NaF sol.), III($SnF_2$ 2 min+APF 2 min+NaF sol.), IV(NaF 2 min+APF 2 min+NaF sol.) and V(APF 4 min+NaF sol.) were significantly greater than group VI.(P<0.05) 2. Microhardness changes of shorter application time of $SnF_2$ (group II) were significantly greater than group III. (P<0.05) 3. Microhardness changes were variable with kinds of fluoride, application sequence and application time of fluoride. but had no relation with the number of fluoride application.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.847-849
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• 1992

Fluorine-doped ($SnO_2$:F) thin films obtained by pyrosol deposition method have been exposed to R.F. excited pure hydrogen plasma under the following conditions; substrate temperature of 200$^{\circ}C$, $H_2$ pressure of 1 Torr, R.F. input power of 50 mW/$\textrm{cm}^{2}$, $H_2$ flow rate of 30cc/min and exposure time of 15-600 seconds. It is found that the sheet resistance of the films remains unchanged or rather slightly reduces for initial exposure time of 30-60 seconds, but increases sharply with further increasing the exposure time. The optical transmittance of $SnO_2$:F films slows a rapid fall with increasing exposure time except for a film obtained with a solution having $CH_3OH/H_2O$ mol ratio of 2.65, its degradations at the exposure time of 30-60 seconds are about 7-15%. In addition, the exposure of the films to hydrogen plasma atmosphere leads to remarkable changes in the microstructure and chemical composition, which should be attributed to the reduction of $SnO_2$ to SnO and to elemental Sn.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.209-215
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• 2002

This study investigated the crystal growth, crystalline structure and the basic optical properties of $SnSe/BaF_2$ epilayers. The SnSe epilayer was grown on $BaF_2$(111) insulating substrates using a hot wall epitaxy(HWE) technique. It was found from the analysis of X-ray diffraction patterns that $SnSe/BaF_2$ epilayer was growing to single crystal with orthorhombic structure oriented [111] along the growth direction. Using Rutherford back scattering(RBS), the atomic ratios of the SnSe was found to be stoichiometric, almost 50 : 50. The best values for the full width at half maximum (FWHM) of the DCXRD was 163 arcsec for SnSe epilarer. The epilayer-thickness dependence of the FWHM of the DCXRD shows that the quality of the $SnSe/BaF_2$ is as expected. The dielectric function ${\varepsilon}$(E) of a semiconductor is closely related to its electronic energy band structure and such relation can be drawn from features around the critical points in the optical spectra. The real and imaginary parts(${\varepsilon}_1$ and ${\varepsilon}_2$) of the dielectric function ${\varepsilon}$ of SnSe were measured. These data are analyzed using a theoretical model known as the model dielectric function(MDF). The optical constants related to dielectric function such as the complex refractive index(n*-n+ik), absorption coefficient (${\alpha}$) and normal- incidence reflectivity (R) are also presented for $SnSe/BaF_2$.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.35-41
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• 2004

This study investigated the crystal growth, crystalline structure and the basic optical properties of $PbSnSe/BaF_2$ epilayers. The PbSnSe epilayer was grown on $BaF_2$(111) insulating substrates using a hot wall epitaxy (HWE) technique. It was found from the analysis of X-ray diffraction patterns that $PbSnSe/BaF_2$ epilayer was grown single crystal with a rock-salt structure oriented along [111] the growth direction. Using Rutherford back scattering, the atomic ratios of the PbSnSe was found to be proper stoichiometric. The best values for the full width at half maximum (FWHM) of the DCXRD was 162 arcsec for PbSnSe epilayer. The epilayer-thickness dependence of the FWHM of the DCXRD shows that the quality of the $PbSnSe/BaF_2$ is as expected. The dielectric function ${\varepsilon}(E)$ of a semiconductor is closely related to its electronic energy band structure and such relation can be drawn from features around the critical points(CPs) in the optical spectra. The real and imaginary parts(${\varepsilon}1$ and ${\varepsilon}2$) of the dielectric function ${\varepsilon}$ of PbSe were measured, and the observed spectra reveal distinct structures at energies of the E1, E2 and E3 CPs. These data are analyzed using a theoretical model known as the model dielectric function (MDF). The optical constants related to dielectric function such as the complex refractive index ($n^*=n+ik$), absorption coefficient (${\alpha}$) and normal-incidence reflectivity (R) are also presented for $PbSnSe/BaF_2$.