• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.367-368
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• 2007

To investigate the 2nO thin films which are interested in the next generation of short wavelength LEDs and Lasers and UV photodetector with p-type inversion layer, the ZnO thin films were deposited by RF sputtering system. Gas ratios and work pressure is Ar : $O_2$ = 4 : 1 and 15 mTorr, respectively, and the purity of ZnO target is 5N. The ZnO thin films were deposited at 300, 450, and $650^{\circ}C$. The current-voltage, responsivity and quantum efficiency of devices were studied and compared with each devices.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.211.1-211.1
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• 2013

We fabricate the conductive zinc oxide(ZnO) thin film using UV-enhanced atomic layer deposition. ZnO is semiconductor with a wide band gap(3.37eV) and transparent in the visible region. ZnO can be deposited with various method, such as metal organic chemical vapour deposition, magnetron sputtering and pulsed laser ablation deposition. In this experiment, ZnO thin films was deposited by atomic layer deposition using diethylzinc (DEZ) and D.I water as precursors with UV irradiation during water dosing. As a function of UV exposure time, the resistivity of ZnO thin films decreased dramatically. We were able to confirm that UV irradiation is one of the effective way to improve conductivity of ZnO thin film. The resistivity was investigated by 4 point probe. Additionally, we confirm the thin film composition is ZnO by X-ray photoelectron spectroscopy. We anticipate that this UV-enhanced ZnO thin film can be applied to electronics or photonic devices as transparent electrode.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.252.1-252.1
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• 2013

Hexagonal boron nitride (h-BN) is a two dimensional material which has high band-gap, flatness and inert properties. This properties are used various applications such as dielectric for electronic device, protective coating and ultra violet emitter so on. 1) In this report, we were growing h-BN sheet directly on sapphire 2"wafer. Ammonia borane (H3BNH3) and nickel were deposited on sapphire wafer by evaporate method. We used nickel film as a sub catalyst to make h-BN sheet growth. 2) During annealing process, ammonia borane moved to sapphire surface through the nickel grain boundary. 3) Synthesized h-BN sheet was confirmed by raman spectroscopy (FWHM: ~30cm-1) and layered structure was defined by cross TEM (~10 layer). Also we controlled number of layer by using of different nickel and ammonia borane thickness. This nickel film supported h-BN growth method may propose fully and directly growing on sapphire. And using deposited ammonia borane and nickel films is scalable and controllable the thickness for h-BN layer number controlling.

• 한국수소및신에너지학회논문집
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• 제32권5호
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• pp.340-346
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• 2021

The initial electrochemical performance of ceramic fuel cell with thin-film electrolyte fabricated by plasma-enhanced atomic layer deposition method was evaluated in terms of peak power density ratio, open circuit voltage ratio, and activation/ohmic resistance ratios at 500℃. Hydrogen and air were used as anode fuel and cathode fuel, respectively. The peak power density ratio reduced as ~52% for 30 min, which continually decreased as time increased but degradation rate gradually decreased. The open circuit voltage ratio decreased with respect time; however, its behavior was evidently different from the reduction behavior of the peak power density. The activation resistance ratio increased as ~127% for 30 min, which was almost similar with the reduction behavior of the peak power density ratio.

• 대한금속재료학회지
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• 제49권3호
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• pp.256-263
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• 2011

We have synthesized Al-Co/AlN-Co multilayer films with different layer thicknesses by using a Two-Facing Target Type dc Sputtering (TFTS) system. The deposited films were annealed isothermally at different temperatures and their microstructure, magnetic properties and resistivity were investigated. The magnetization of the as-deposited films was found to be very small, irrespective of layer thickness. It was found that the annealing conditions and layer thickness ratio of Al-Co to AlN-Co (LTR) were able to control the microstructure, as well as the physical properties of the prepared films. The resistivity and magnetization increased and the coercivity decreased with a decreasing LTR. A high resistivity of 2500 ${\mu}{\Omega}-cm$, a magnetization of 360 $emu/cm^3$, and a coercivity of 5 Oe were obtained for the films with LTR=0.175.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.21-26
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• 2004

Deposition condition of YBa$_2$Cu$_3$$O_{7-x}$ (YBCO) films on moving IBAD templates (CeO$_2$/IBAD-YSZ/SS) was studied in a hot-wall type metal organic chemical vapor deposition (MOCVD) process using single liquid source. The reel velocity was 40 cm/hr and the source mole ratios of Y(tmhd)$_3$:Ba(tmhd)$_2$:Cu(tmhd)$_2$ were 1:2.3:3.1 and 1:2.1:2,9, Two different types of IBAD templates with thin CeO$_2$ and thick CeO$_2$ layers were used, The YBCO films were successfully deposited at the deposition temperatures of 780~89$0^{\circ}C$ ; the a-axis growth was observed together with the c-axis growth up to 83$0^{\circ}C$. while the c-axis growth became dominant above 83$0^{\circ}C$. The top surface of the c-axis film was fairly dense and included a small amount of the a-axis growth, although the peaks of the a-axis grains were not observed in XRD pattern, The YBCO film deposited on IBAD template with thin CeO$_2$ layer showed low critical current of 2.5 A/cm-width. while the YBCO film deposited on IBAD template with thick CeO$_2$ layer showed higher critical current of 50 A/cm-width. This result indicates that thick CeO$_2$ layer is thermally more stable than thin CeO$_2$ layer at the high deposition temperature of the MOCVD process.s.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2007년도 춘계학술대회
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• pp.193-198
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• 2007

The NiSi is very promising candidate for the metallization in 60nm CMOS process such as FUSI(fully silicided) gate and source/drain contact because it exhibits non-size dependent resistance, low silicon consumption and mid-gap workfunction. Ni film was first deposited by using ALD (atomic layer deposition) technique with Bis-Ni precursor and $H_2$ reactant gas at $220^{\circ}C$ with deposition rate of $1.25{\AA}/cycle$. The as-deposited Ni film exhibited a sheet resistance of $5{\Omega}/{\square}$. RTP (repaid thermal process) was then performed by varying temperature from $400^{\circ}C$ to $900^{\circ}C$ in $N_2$ ambient for the formation of NiSi. The process window temperature for the formation of low-resistance NiSi was estimated from $600^{\circ}C$ to $800^{\circ}C$ and from $700^{\circ}C$ to $800^{\circ}C$ with and without Ti capping layer. The respective sheet resistance of the films was changed to $2.5{\Omega}/{\square}$ and $3{\Omega}/{\square}$ after silicidation. This is because Ti capping layer increases reaction between Ni and Si and suppresses the oxidation and impurity incorporation into Ni film during silicidation process. The NiSi films were treated by additional thermal stress in a resistively heated furnace for test of thermal stability, showing that the film heat-treated at $800^{\circ}C$ was more stable than that at $700^{\circ}C$ due to better crystallinity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.316-316
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• 2008

Using an evaporation method, $SiO_2$ was deposited as a buffer layer between a flexible PET substrate and a ITO film deposited by DC magnetron sputtering and electro-optical properties were investigated with thickness variance of $SiO_2$ layers. After coating a $SiO_2$ layer and a ITO film, the ITO/$SiO_2$/PET was heated up to $200^{\circ}C$ and the resistivity and the transmittance were measured by hall effect measurement system and UV/VIS/NIR spectroscopy. As a result of depositing a $SiO_2$ buffer layer, the resistivity increased and the transmittance and adhesion property were enhanced than ITO films with no buffer layers and the resistivity was lowered as $SiO_2$ thickness increased from 50 $\AA$ to 100 $\AA$. It was found that the transmittance was independent of annealing temperature variance in $150^{\circ}C{\sim}200^{\circ}C$ and the resistivity decreased as the temperature increased and especially decreasing rate of the resistivity was higher as the buffer layer thickness was thinner. So under optimized depositing of $SiO_2$ buffer layers and post-annealing of ITO/$SiO_2$/PET, ITO films with enhanced adhesion, electro-optical properties can obtained.

• 한국진공학회지
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• 제14권4호
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• pp.201-206
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• 2005

본 연구에서는 HVPE (Hydride Vapor Phase Epitaxy) 방법으로 Si 위에 GaN/AIN/Al/Si 구조를 제작하고, AlN 버퍼층의 두께에 따른 광학적 특성을 조사함으로써 효과적인 eaN 성장을 위한HVPE에서의 공정 방법을 개선하고자 하였다. 이를 위해 Al을 증착한 Si 기판과 그렇지 않은 경우를 PL측정을 통해 그 효과를 관찰하였고, $5{\AA}$ 두께의 Al 대해 AlN 버퍼층의 두께를 변화시켜가면서 GaN를 성장시켜 그 특성을 조사하였다. Al을 증착한 경우가 증착하지 않은 경우에 비해 광학적 특성이 우수한 것으로 나타났으며, AlN의 두께 변화에 대해서는 양질의 GaN를 얻기 위한 최적의 두께는 약 $260{\AA}$ 인 것으로 나타났다. 이 경우 SEM을 이용한 표면사진에서 GaN의 초기성장이 hexagonal형태로 성장되고 있음을 관찰할 수 있었다. 또한 XRD의 회절 패턴은 GaN가 {0001} 방향으로 우선 배향성을 가지고 성장되고 있음을 보여주고 있었다.

• 한국진공학회지
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• 제12권4호
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• pp.263-268
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• 2003

차세대 반도체 및 디스플레이 소자에 적용되는 실리콘 질화막은 정확한 두께 제어와 우수한 물성을 필요로 한다. 본 연구에서는 우수한 특성의 실리콘 질화막을 형성하기 위해 Si 원료물질로 $SiC1_4$, N 원료물질로 $NH_3$을 사용하고 $500^{\circ}C$에서 $600^{\circ}C$ 온도구간에서 batch-type 장비를 이용하여 원자층 증착 방법으로 박막을 형성하고 증착된 박막의 특성을 살펴보았다. Batch-type 장비를 사용한 박막의 증착은 표면반응에 의한 균일한 원자층 증착임을 확인하였으며, 증착 cycle의 횟수를 조절하여 원하는 두께의 박막을 형성할 수 있었다. 원자층 증착된 박막의 조성, 굴절률 및 습식각 속도를 기존의 저압화학증착 방법에 의해 증착된 박막과 비교한 결과, 원자층 증착 방법을 사용하여 기존의 방법보다 증착온도를 $250^{\circ}C$ 이상 낮추면서도 유사한 물성을 가진 박막을 형성할 수 있음을 확인하였다. Pyridine을 촉매로 첨가하여 원자층 증착한 박막의 경우에는 증착속도를 50% 가량 향상시킬 수 있었으나 박막의 구조가 불안정하여 쉽게 산화되므로 반도체나 디스플레이 소자 제조에 적용하기에는 부적절한 것으로 판단된다.