• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1456-1458
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• 1998

The $(Sr_{1-x}Ca_x)TiO_3(SCT)$ thin films were deposited at various substrate temperature using rf magnetron sputtering method on optimized Pt-coated electrodes ($Pt/TiN/SiO_2/Si$). The dielectric constant changes almost linearly in the temperature region of $-80{\sim}+90[^{\circ}C]$, the temperature characteristics of the dielectric loss exhibited a stable value within 0.1. The capacitance characteristics appears a stable value within ${\pm}5$[%]. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films is observed above 200[kHz]. Dielectric constant of SCT thin films deposited on Si wafer substrate are larger with the increase of deposition temperature.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1540-1542
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• 1997

Plasma polymerized thin films were fabricated by interelectrode capacitively coupled type apparatus. FT-IR analyses indicated that the thin film spectra are composed not only of the corresponding monomer bands but also of several new bands. Relative dielectric constant and dielectric loss tangent of thin films fabricated in the discharge power of 90[W] showed $3.212{\sim}3.805$ and $0.0026{\sim}0.0451$ in alternating frequency of $10^3{\sim}10^6$[Hz]. Contact angle measurement indicated that cross-link of the films is increased with the discharge power.

• 한국응용과학기술학회지
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• 제18권1호
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• pp.49-54
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• 2001

Ultra-thin films of organic charge transfer complex were prepared on a hydrophilic substrate by Langmuir-Blodgett(LB) technique. In this study, the photoelectric properties of a LB film consisting of (N-docosyl quinolinium)-TCNQ(1:2) complex was investigated. The visible light(${\lambda}$ : 700 nm) of xenon lamp was illuminated on the LB films and light absorptivity and photoconductivity were observed. The photocurrent increased linearly and was saturated at the light intensity of 23 ${\mu}W/cm^{2}$.

• Journal of Ceramic Processing Research
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• 제13권spc2호
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• pp.394-397
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• 2012

In this work, we studied the influence of the dopant elements concentration on the properties of SnO2 thin films deposited by pulsed laser deposition. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Hall effect measurement and UV-Vis studies were performed to characterize the deposited films. XRD results showed that the films had polycrystalline nature with tetragonal rutile structure. FE-SEM micrographs revealed that the as deposited films composed of dense microstructures with uniform grain size distribution. All the films show n-type conduction and the best transparent conductive oxide (TCO) performance was obtained on 6 wt% Sb2O5 doped SnO2 film prepared at pO2 of 60mtorr and Ts of 500 ℃. Its resitivity, optical transmittance, figure of merit are 7.8 × 10-4 Ω cm, 85% and 1.2 × 10-2 Ω-1, respectively.

• 센서학회지
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• 제19권3호
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• pp.209-213
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• 2010

This paper describes the fabrication and characteristics of AlN piezoelectric MPG(micro power generator). The micro energy harvester was fabricated to convert ambient vibration energy to electrical power as a AlN piezoelectric cantilever with Si proof-mass. To be compatible with CMOS process, AlN thin film was grown at low temperature by RF magnetron sputtering and micro power generators were fabricated by MEMS technologies. X-ray diffraction pattern proved that the grown AlN film had highly(002) orientation with low value of FWHM(full width at the half maximum, $\theta=0.276^{\circ}$) in the rocking curve around(002) reflections. The implemented harvester showed the $198.5\;{\mu}m$ highest membrane displacement and generated 6.4 nW of electrical power to $80\;k{\Omega}$ resistive load with $22.6\;mV_{rms}$ voltage from 1.0 G acceleration at its resonant frequency of 389 Hz. From these results, the AlN piezoelectric MPG will be possible to suitable with the batch process and confirm the possibility for power supply in portable, mobile and wearable microsystems.

• Progress in Superconductivity
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• 제3권1호
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• pp.23-27
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• 2001

We have investigated the mixed-state magnetoresistance of high quality c-axis-oriented MgB2 thin film for magnetic field from 0.5 T to 5.0 T, applied normal to ab-plane. The temperature dependence of magnetoresistance was well described by vortex glass and fluctuation theories for different temperature regimes. We observed glassy exponent of v(z-1)~3 and upper critical field of $H_{c2}$(0)~35 T, which is consistent with previous data obtained from direct $H_{c2}$(0) measurements. Interestingly, the thermally activated flux flow region was observed to be very narrow, suggesting that the pinning strength of this compound is very strong. This finding is closely related to the recent reports that the bulk pinning is dominant in $MgB_2$and the critical current density of $MgB_2$ thin film is very high, comparable to that of cuprate superconductor. The present results further suggest that $MgB_2$is beneficial to technical applications.ons.

• Transactions on Electrical and Electronic Materials
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• 제12권2호
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• pp.60-63
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• 2011

We investigated the etching characteristics of zinc oxide (ZnO) and the effect of additive gases in a $Cl_2$-based inductively coupled plasma. The inert gases were argon, nitrogen, and helium. The maximum etch rates were 44.3, 39.9, and 37.9 nm/min for $Cl_2$(75%)/Ar(25%), $Cl_2$(50%)/$N_2$(50%), and $Cl_2$(75%)/He(25%) gas mixtures, 600 W radiofrequency power, 150 W bias power, and 2 Pa process pressure. We obtained the maximum etch rate by a combination of chemical reaction and physical bombardment. A volatile compound of Zn-Cl. achieved the chemical reaction on the surface of the ZnO thin films. The physical etching was performed by inert gas ion bombardment that broke the Zn-O bonds. The highly oriented (002) peak was determined on samples, and the (013) peak of $Zn_2SiO_4$ was observed in the ZnO thin film sample based on x-ray diffraction spectroscopy patterns. In addition, the sample of $Cl_2$/He chemistry showed a high full-width at half-maximum value. The root-mean-square roughness of ZnO thin films decreased to 1.33 nm from 5.88 nm at $Cl_2$(50%)/$N_2$(50%) plasma chemistry.

• 대한전자공학회논문지SD
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• 제37권2호
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• pp.5-12
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• 2000

열전퇴의 고온 접합부가 Si/sub 3/N/sub 4//SiO/sub 2//Si/sub 3/N/sub 4/ 멤브레인에 의해 실리콘 기판으로부터 열차단되고, 열전퇴의 저온 접합부는 방열판 역할을 하는 실리콘 림(rim)에 의해 지지되는 멤브레인위에 놓여지며, Au-black이 적외선 흡수체로 사용되는 비냉각 금속 박막형 열전퇴 적외선 검지기를 제작하고, 적외선 검지기의 성능지수에 대해 논의하였다. 3∼14㎛의 파장범위에서 Au-black의 적외선 흡수도는 대개 90%정도였고, Au 증발시의 챔버압력 및 증착된 Au-black의 단위면적당 질량에 크게 의존하였다. 쵸핑 주파수가 5 Hz일 때 Bi-Sb 열전퇴 적외선 검지기의 전압 감응도, 잡음등가전력 및 비검지도는 실온의 공기중에서 각각 약 10.5V/W, 2.3 ㎻/㎐½, 및 1.9×10/sup 7/㎝·㎐½/w였다.

• 센서학회지
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• 제7권4호
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• pp.279-284
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• 1998

수용액에서 자당의 농도 변화를 감지하기 위한 센서개발을 목적으로 하여, 금박막을 센서칩으로 사용한 SPR(surface plasmon resonance) 센서시스템을 구성하였다. 센서칩 제작시 금박막의 특성조건은 SPR 현상에 매우 큰 영향을 미치므로, 센서 제작의 최적화를 위해 특성을 분석하여 두께 약 $545\;{\AA}$, 표면 평균 거칠기 약 $3\;{\AA}$이 되도록 균일하게 제작하였다. 이렇게 제작된 금박막 센서칩의 공명각은 $43.75^{\circ}$ 이었으며, $0{\sim}40\;wt%$ 농도의 자당 수용액을 측정한 결과 기존의 알려진 자당 센서에 비해 빠른 응답특성과 선형적인 공명특성을 얻을 수 있었다.

• 한국표면공학회지
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• 제46권4호
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• pp.168-174
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• 2013

In this study, low-cost, high-speed deposition, excellent processability, high mechanical strength and electrical conductivity, chemical stability and corrosion resistance of stainless steel to meet the obsessive-compulsive (0.1 mm or less) were selected CrN thin film. new price reduction to sputter deposition causes - the possibility of sublimation source for inductively coupled plasma Cr rods were attempts by DC bias. 0.6 Pa Ar inductively coupled plasmas of 2.4 MHz, 500 W, keeping Cr Rod DC bias power 30 W (900 V, 0.02 A) is applied, $N_2$ flow rate of 0.5, 1.0, 1.5 sccm by varying the characteristics of were analyzed. $N_2$ flow rate increases, decreases and $Cr_2N$, CrN was found to increase. In addition to corrosion resistance and contact resistance, corrosion resistance, electrical conductivity was evaluated. corrosion current density than $N_2$ 0 sccm was sure to rise in all, $N_2$ 1 sccm at $4.390{\times}10^{-7}$ (at 0.6 V) $A{\cdot}cm^{-2}$, respectively. electrical conductivity process results when $N_2$ 1 sccm 28.8 $m{\Omega}/cm^2$ with the lowest value of the contact resistance was confirmed that came out. The OES (SQ-2000) and QMS (CPM-300) using a reactive deposition process to add $N_2$ to maintain a uniform deposition rate was confirmed that.