• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.290-294
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• 2001

In this study, ZnO is evaporated to be coated on n-type Si wafer substrate. Refractive coefficient of thin film that is evaporating TiO$_2$ onto ZnO increases linearly as thickness is getting thinner to have high value and high angle and it satisfies theoretical equation I(x)=Io exp (-$\alpha$x) theory that represents the strength of photon energy advancing through ZnO thin film. And dielectric constant of TiO$_2$ thin film evaporated onto ZnO is high and $\varepsilon$$_2$ is smaller than $\varepsilon$$_1$. The specimen TiO$_2$ thin film evaporated onto ZnO has much higher dielectric constant when photon energy is increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.9
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• pp.681-684
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• 2010

The $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ multilayered structure for the transparent electrodes in plasma display panel was designed by essential macleod program (EMP) and the multilayered film was deposited on a glass substrate by direct-current (DC)/radio-frequency (RF) magnetron sputtering system. During film deposition process, the Ag layer in $TiO_2$/Ag/$TiO_2$ structure became oxidized and the filter characteristic was degraded easily. In this study, ZnS layer was adopted as a diffusion blocking layer between $TiO_2$ and Ag to prevent the oxidation of Ag layer efficiently in $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ structure. Based on the AES depth profiling analysis, the Ag layer was effectively protected by the ZnS layer as compared with the $TiO_2$/Ag/$TiO_2$ multilayered films without ZnS as an antioxidant layer. The 3 times stacked $TiO_2$/ZnS/Ag/ZnS/$TiO_2$ films have low sheet resistance of $1.22{\Omega}/{\square}$ and luminous transmittance was as high as 62% in the visible ranges.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.10
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• pp.837-843
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• 2009

$TiO_2$(2 wt.%)-doped ZnO(TZO) films with thickness from 100 nm to 500 nm were prepared on polyethylene naphthalate(PEN) substrate under various rf-power range from 40 W to 80 W. Their electrical and optical properties were investigated as a function of rf-power. We think that these properties were closely related with the crystallization and the film density of TZO films. It was also presumed that the vaporization of the water vapor and other adsorbed particles such as an organic solvents can affect the electrical properties of the conventional transparent conductive oxide(TCO) films. On the other hand, since the TZO film deposited on glass substrate at room temperature with rf-power of 80 W shows a very low resistivity of $7.5\times10^{-4}\;\Omega{\cdot}cm$ and a very excellent transmittance over an average 85% in the visible range, that is comparable to that of ITO films. Therefore, we expect that the TZO films can be used as transparent electrode for optoelectronic devices such as touch-panels, flat-panel displays, and thin-film solar cells.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.6
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• pp.127-135
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• 1996

To increase the sensitivity and the selectivity of the sensors to TMA gas, the composition ratio and the growth conditions of the ZnO films are studied. Annealing of the ZnO films in the various time ranges and temperatures in the oxygen is carried out to enhance the stbility of the electrical resistance. Pt/Ti heater deposited on backside of the substrates in used to control the operating temperature of th esensor. The ZnO thin film sensors doped to 4.0 wt% $Al_{2}$O$_{3}$ 1.0wt.% TiO$_{2}$ and 0.2wt.% V$_{2}$O$_{5}$ exhibited a high sensitivity and an excellent selectivity for TMA gas. The sensors made with the thin films annealed at 700$^{\circ}$C for 60 minutes in the oxygen atmosphere had a good stability and linearity. The heater deposited in the ratio of 1 to 1 (Pt:Ti) had a good heating properties. The sensors fabricated using above conditions showed a good response to the actual gases of a mackerel at a step of deterioration after death.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.898-901
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• 2004

[ $ZnCr_2O_4$ ]를 모물질로 하고 MgO, $TiO_2$를 몰비로 2:1, 4:1, 6:1, 및 8:1이 되게 정량적으로 조합한 후, 조사하였다. $ZnCr_2O_4$-MgO와 $ZnCr_2O_4-TiO_2$를 X-선 분석한 결과 Spinel 결정구조를 형성하였으며, 또한 SEM과 EDX 분석결과 각각 $Li_2CrO_4$와 $Li_3VO_4$의 형성으로 인하여 저항 특성이 나타나는 것을 알 수 있었다. $ZnCr_2O_4-MgO$, $ZnCr_2O_4-TiO_2$에서 MgO의 양이 증가할수록 저항값은 약간 감소하는 반면, $TiO_2$의 양이 증가할수록 저항값이 급격히 증가하는 특성을 나타내었고, 감습 특성에서도 M??보다 TiO2가 더 높게 나타내었다. 습에 따른 복원 특성의 경우 $700^{\circ}C$에서 소결한 ($ZnCr_2O_4:MgO=4:1$)과 ($ZnCr_2O_4:TiO_2=6:1$) 조성의 센서가 가장 양호하였다.

• Transactions on Electrical and Electronic Materials
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• v.14 no.2
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• pp.86-89
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• 2013

Dye-sensitized solar cells have a FTO/$TiO_2$/Dye/Electrode/Pt counter electrode structure, yet more than a 10% electron loss occurs at each interface. A passivating layer between the $TiO_2$/FTO glass interface can prevent this loss of electrons. In theory, ZnO has excellent electron collecting capabilities and a 3.4 eV band gap, which suppresses electron mobility. FTO glass was coated with ZnO thin films by RF-magnetron sputtering; each film was deposited under different $O_2$:Ar ratios and RF-gun power. The optical transmittance of the ZnO thin film depends on the thickness and morphology of ZnO. The conversion efficiency was measured with the maximum value of 5.22% at an Ar:$O_2$ ratio of 1:1 and RF-gun power of 80 W, due to effective prevention of the electron recombination into electrolytes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.277-277
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• 2010

We present facile chemical route stabilizing dispersion of carboxylated single-Walled carbon nanotubes (SWCNTs) in ZnOsol prepared by using diethanolamine as a stabilizer. The dispersion was stabilized via capping of carboxyl groups on the SWCNT surface by a titania layer. We also demonstrated that the conductivity of the films prepared P3/$TiO_2$/ZnO as enhanced by therml treatment, and the thermal stbility of the film improved hybridization with ZnO sol pristine P3, P3/$SiO_2$ and P3/$TiO_2$ hybrid films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.41-41
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• 2010

We present facile chemical route stabilizing dispersion of carboxylated single-walled carbon nanotubes (SWCNTs) in ZnOsol prepared by using diethanolamine as a stabilizer. The dispersion was stabilized via capping of carboxyl groups on the SWCNT surface by a titania layer. We also demonstrated that the conductivity of the films prepared P3/$TiO_2$/ZnO as enhanced by therml treatment, and thethermal stbility of the film improved hybridization with ZnO sol pristine P3, P3/$SiO_2$ and P3/$TiO_2$ hybrid films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1092-1095
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• 2004

The $ZnGa_2O_4$ phosphor target is synthesized through solid-state reactions as calcine and sintering temperature in order to deposit $ZnGa_2O_4$ phosphor thin film by rf magnetron sputtering system. The $ZnGa_2O_4$ phosphor thin film is deposited on $Pt/Ti/SiO_2/Si$ substrate and prepared $ZnGa_2O_4$ Phosphor thin film is annealed by rapid thermal processor(RTP) at $750^{\circ}C$, 10 sec. The x-ray diffraction patterns of $ZnGa_2O_4$ phosphor target and thin film show the position of (311) main peak. The cathodolumincsccnce(CL) succtrums of $ZnGa_2O_4$ phosphor target show main peak of 360nm and broad bandwidth of about 180nm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.91-95
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• 2012

ZnO thin films were deposited on p-type 4H-SiC substrate by pulsed laser deposition. ZnO nanowires were formed on p-type 4H-SiC substrate by furnace. Ti/Au electrodes were deposited on ZnO thin film/SiC and ZnO nanowire/SiC structures, respectively. Structural and crystallographical properties of the fabricated ZnO thin film/SiC and ZnO nanowire/SiC structures were investigated by field emission scanning electron microscope and X-ray diffraction. In this work, resistance and sensitivity of ZnO thin film/SiC gas sensor and ZnO nanowire/SiC gas sensor were measured at $300^{\circ}C$ with various CO gas concentrations (0%, 90%, 70%, and 50%). Resistance of gas sensor decreases at CO gas atmosphere. Sensitivity of ZnO nanowire/SiC gas sensor is twice as big as sensitivity of ZnO thin film/SiC gas sensor.