• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1293-1294
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• 2007

태양전지는 대표적인 결정질 실리콘 태양전지를 비롯해 다양한 종류가 있지만 모두 입사광의 광량이나 광도에 출력이 의존한다는 점은 공통적이다. 이는 입사광의 에너지를 받아 염료 분자의 여기를 통해 전자를 생산하는 염료감응형 태양전지의 매커니즘에도 적용되는 것이다. 즉, 입사광의 광도나 광량의 값이 클수록 염료감응형 태양전지는 더 높은 출력전력을 생산한다는 의미이다. 본 연구에서는 투명성 때문에 입사광의 투과도가 높은 염료감응형 태양전지의 특성에 착안해 상대전극에 금속박막을 sputtering함으로써 입사광의 반사율을 증가시켜 입사된 광의 에너지를 더 효과적으로 활용할 수 있는 방법을 시도했다. 금속박막의 재료로 니켈, 백금, 은을 대상으로 실험한 결과, 금속박막을 sputtering 하지 않은 경우에 비해 전체적으로 염료감응형 태양전지의 효율이나 전력면에서 개선된 결과를 얻었고 그 중 백금 반사막을 입힌 셀로부터 최대 24.4%의 투과도 감소를 비롯, 11.5%의 출력전력의 증가와 0.4%의 효율 상승을 이끌어냈다.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.54-54
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• 1992

ITO투명전극/WO$_3$박막/LiClO$_4$-PC/백금 대향전극 구조를 갖는 일렉트로 크로믹 소자를 구성하여 WO$_3$박막의 일렉트로크로믹 특성을 조사하였다. WO$_3$박막의 coloration의 LiClO$_4$-PC 유기전해질과 ITO 투명전극으로부터 Li$^{+}$이온과 전자들의 이중주입에 의하여 청색으로 나타났으며, 전기화학전인 산화반응에 의하여 bleaching 현상이 가역적으로 일어났다. Coloration 과 bleaching 현상, 광학밀도, 구동전압 및 응담속도등의 일렉트로크로믹 특성은 WO$_3$ 박막의 성장 조건, WO$_3$박막 두께, ITO 투명전극의 sheet resistance, 대향전극 및 인가전압에 크게 의존하는 것으로 밝혀졌다.

• Journal of the Microelectronics and Packaging Society
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• v.1 no.2
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• pp.113-124
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• 1994

MOD법을 마이크로회로용 티탄산 바륨 콘덴서 박막형성에 적용하였다. Barium decanoate barium 2-ethylhexanoate titanium dimethoxy didecanoate 및 titanium dimethoxy di-2-ethylhexanoate와 같은 여러 가지 금속유기화합물들을 합성하고 동정한 다 음 공통용매에 대한 용해도를 시험하였다. 이금속유기화학물들 가운데 barium 2-ethylhexanoate와 titanium dimethoxy di-2-ethylhexanoate가 xylene-pyridine 혼합용매에 잘녹고 MOD법에 의한 BaTiO3 박막형성에 매우 안정한 조성을 이룸을 확인하였다. 이 조 성을 스핀코팅에 의하여 백금박과 실리콘 웨이퍼상에 금속유기화학물 막을 형성하고 최고 온도와 유지시간에 따라 소성하여 형성된 유전체 박막들의 전기전 특성을 측정하고 고찰하 였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.931-935
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• 2012

In this study, we fabricate and investigate low-temperature solid oxide fuel cells with a ceramic substrate/porous metal/ceramic/porous metal structure. To realize low-temperature operation in solid oxide fuel cells, the membrane should be fabricated to have a thickness of the order of a few hundreds nanometers to minimize IR loss. Yttrium-doped barium zirconate (BYZ), a proton conductor, was used as the electrolyte. We deposited a 350-nm-thick Pt (anode) layer on a porous substrate by sputter deposition. We also deposited a 1-${\mu}m$-thick BYZ layer on the Pt anode using pulsed laser deposition (PLD). Finally, we deposited a 200-nm-thick Pt (cathode) layer on the BYZ electrolyte by sputter deposition. The open circuit voltage (OCV) is 0.806 V, and the maximum power density is 11.9 mW/$cm^2$ at $350^{\circ}C$. Even though a fully dense electrolyte is deposited via PLD, a cross-sectional transmission electron microscopy (TEM) image reveals many voids and defects.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.152-155
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• 1996

Platinum thin films were deposited on $Al_2$O$_3$substrate by DC magnetron sputtering for RTD(Resistance Thermometer Devices) temperature sensors. We made Pt resistance pattern on $Al_2$O$_3$substrate by lift-off method and fabricated Pt-RTD temperature sensors by using W-wire, silver epoxy and SOG(spin-on-glass). In the temperature range of 25~40$0^{\circ}C$, we investigated TCR(temperature coefficient of resistance) and resistance ratio of Pt-RTD temperature sensors. TCR values were increased with increasing the annealing temperature, time and the thickness of Pt thin films. Resistance values were varied lineally within the range of measurement temperature. At annealing temperature of 100$0^{\circ}C$, annealing time of 240min and thin film thickness of 1${\mu}{\textrm}{m}$, we obtained Pt-RDT TCR value of 3825ppm/$^{\circ}C$ closed to the Pt bulk value.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.150-153
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• 1999

The electrical and physical characteristics of MgO and Pt thin-films on Si wafers deposited by r.f magnetron sputtering, were analyzed with annealing condition(100$0^{\circ}C$, 120 min) by four point probe, SEM and XRD. Until annealing temperature of 100$0^{\circ}C$, MgO had the properties of improving Pt adhesion to SiO$_2$ and insulation without chemical reaction to Pt thin-films and the resistivity of Pt thin-films was improved. The thermal characteristics of Pt micro-heater were analyed with Pt-RTD integrated on the same substrate, In the analysis of properties of Pt-RTD, TCR value had 3927 ppm/$^{\circ}C$ and liner in the temperature range of 25~40$0^{\circ}C$ temperature of Pt micro-heater had up to 40$0^{\circ}C$ with 1.5 watts of the heating power.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.358-361
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• 1999

This paper describes on the fabrication and characteristics of hot-film type micro-flowsensors integrated with Pt-RTD\`s and micro-heater on the Si substrate, in which MgO thin-films were used as medium layer in order to improve adhesion of Pt thin-films to SiO$_2$ layer The MgO layer improved adhesion of Pt thin-films to SiO$_2$` layer without any chemical reactions to Pt thin-films under high as gas flow rate and its conductivity increased due to increase of heat-loss from sensor to external. Output voltage was 82 mV at N2 flow rate of 2000 sccm/min, heating power of 1.2W. The respons time was about 100 msec when input flow was step-input

• Korean Journal of Materials Research
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• v.10 no.5
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• pp.360-363
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• 2000

Deformation in the hysteresis loop of $Pb(Zr,Ti)O_3$ (PZT) thin films with various Zr/Ti ratios has been studied by varying the top electrode preparation method and the annealing temperature. Pt/PZT/Pt capacitors was found to be positively poled due to dc plasma potential generated during reactive ion etch (RIE) of Rt. Internal field is formed by space charges trapped at domain boundaries. Aging phenomenon such as constriction in the middle of the hysteresis loop was observed in the PZT film with top electrode deposited by sputtering. Top electrode annealing restores the hysteresis loop by removing the space charges. As Zr/Ti ratio decrease, voltage shift increases and an-nealing temperature at which internal field disappears also increases.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.251-255
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• 2009

Nanocomposites based on coupling $TiO_2$ matrix with nanosized noble metals (Pt,Au) particles exhibited promising photoelectrode properties. The $M/TiO_2$ (M=Pt,Au) nanocomposite thin films were deposited on quartz and ITO glass substrates using a co-sputtering method. $TiO_2$ in rutile form is the dominant crystalline phase for as-deposited nanocomposite films. Along with heat treatment up to $600^{\circ}C$, XRD peaks of the rutile phase as well as those of noble metal increased in intensity and decreased in width, indicating the growth of crystallites. The anodic photocurrents of $M/TiO_2$ (M=Au,Pt) thin films were observed not only in the UV range but also in the visible light range. The photocurrent of the nanocomnosite films extended to the visible light region by dispersion of nano-sized noble metal in the $TiO_2$ matrix.

• Journal of Sensor Science and Technology
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• v.11 no.6
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• pp.358-364
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• 2002

In this paper, we used U.V.(wavelength, 355nm) laser for adjusting Pt thin films temperature sensor to $100{\Omega}$ at $0^{\circ}C$. Internationally, A-class tolerance of temperature sensor is $0.06{\Omega}$ at $0^{\circ}C$. This is under value of $0.15^{\circ}C$, actually, so high-fine trimming technology is essential to this process. The width of trimmed lines was about $10{\mu}m$ and the best trimming of Pt thin films of $1{\sim}1.5{\mu}m$ was carried out with power : 35mW, rep. rate frequency : 200Hz and bite size : $1.5{\mu}m$. And using photolithography process, 96 resistors were fabricated in $2"{\times}2"$ substrate as the proportion of $79{\sim}90{\Omega}$ and $91{\sim}102{\Omega}$ is 42.7% and 57.3%, respectively. As result of trimming resistors to the target value of $109.73{\Omega}$ at $25^{\circ}C$, 82.3% of resistors had the tolerance within ${\pm}0.30{\Omega}$ and the others(17.7%) were within ${\pm}0.06{\Omega}$ of A-class tolerance.