• 환경위생공학
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• 제18권3호통권49호
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• pp.64-68
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• 2003

Measurement of dried deposition for air pollutant was investigated in Gwang-ju Health college area for a year. The average value of air pollutants was investigated three times a month. Measured heavy metals and concentration of mass are not corelated. Heavy metals were thrown up air as state of large particles and they were moved by wind. Deposition of heavy metals and deposition velocities were high in the order of Fe > n > Cu > Pb > Cr and Pb > Fe > Cr > Zn > Cu, respectively. The pattems of deposition velocity of heavy metals for a year were much the same as each other except that Pb is faster than others.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.173-176
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• 1998

Epitaxial Si layers were deposited on n- or p-type Si(100) substrates by hot-wall chemical vapor deposition (CVD) technique using the {{{{ {SiH }_{ 2} {Cl }_{2 } - {H }_{ 2} }}}}chemistry. Thermodynamic calculations if the Si-H-Cl system were carried out to predict the window of actual Si deposition procedd and to investigate the effects of process variables(i.e., the deposition temperature, the reactor pressure, and the source gas molar ratios) on the growth of epitaxial layers. The calculated optimum process conditions were applied to the actual growth runs, and the results were in good agreement with the calculation. The expermentally determined optimum process conditions were found to be the deposition temperature between 900 and 9$25^{\circ}C$, the reactor pressure between 2 and 5 Torr, and source gad molar ration({{{{ {H }_{2 }/ {SiH }_{ 2} {Cl }_{2 } }}}}) between 30 and 70, achieving high-quality epitaxial layers.

• Journal of Korean Vacuum Science & Technology
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• 제2권1호
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• pp.49-54
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• 1998

The effect of deposition paratmeters on the solid-phase crystallization of amorphous silicon films deposited by plasma-enhanced chemical vapor deposition has been investigated by x-ray diffraction. The amorphous silicon films were prepared on Si(100) wafers using SiH4 gas with and without H2 dilution at the substrate temperatures between 12$^{\circ}C$ and 38$0^{\circ}C$. The R. F. powers and the deposition pressures were also varied. After crystallizing at $600^{\circ}C$ for 24h, the films exhibited (111), (220), and (311) x-ray diffraction peaks. The (111) peak intensity increased as the substrate temperature decreased, and the H dilution suppressed the crystallization. Increasing R.F. powers within the limits of etching level and increasing deposition pressures also have enhanced the peak intensity. The peak intensity was closely related to the deposition rate, which may be an indirect indicator of structural disorder in amorphous silicon films. Our results are consistent with the fact that an increase of the structural disorder I amorphous silicon films enhances the grain size in the crystallized films.

• Transactions on Electrical and Electronic Materials
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• 제8권4호
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• pp.153-156
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• 2007

Structural and electrical properties of the fully crystallized-bismuth magnesium niobate ($Bi_2Mg_{2/3}Nb_{4/3}O_7$, BMN) films with 15 mol% excess bismuth deposited on Pt bottom electrode by pulsed laser deposition are characterized for various deposition temperatures. The BMN films were crystallized with a monoclinic structure from $300^{\circ}C$ and the surface roughness slightly decreases with increasing deposition temperature. The capacitance density of the films increases with increasing deposition temperature and especially, films deposited at $400^{\circ}C$ exhibit a capacitance density of approximately $620nF/cm^2$. The crystallized BMN films with approximately 170 nm thickness exhibit breakdown strength above 600 kV/cm (${\leq}10V$) irrespective of deposition temperature and a leakage current density of approximately $2{\times}10^{-8}A/cm^2$ at 590kV/cm (at 10 V).

• 한국재료학회지
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• 제11권5호
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• pp.361-366
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• 2001

TiN barrier 막 위에 metal organic chemical vapor deposition (MOCVD)법으로 Cu막을 증착함에 있어 TiN막 표면을 먼저 세정처리하지 않고 바로 Cu막을 증착하려하면 Cu의 핵생성이 어렵고, 그 결과 연속된 Cu막이 형성되지 못한다. 본 연구에서는 SEM, AES, AFM 등의 분석방법을 사용하여 TiN 막 표면에 대한 플라즈마 전처리 세정이 Cu막의 핵생성에 미치는 효과에 관하여 조사하였다. Gu의 전처리 세정방법으로는 direct플라즈마 방식이 원거리 플라즈마 방식보다 훨씬 더 효과적이다. 또한 수소플라즈마 전처리 시 rf-power와 플라즈마 조사시간이 증가함에 따라 세정효과는 더 증대된다. 플라즈마 전처리가 Cu의 핵생성을 고양시키는 원리는 다음과 같다. 플라즈마 내의 수소이온이 TiN과 반응하여 $NH_3$가 됨으로서 질소 성분이 제거되어 TiN이 Ti로 환원된다. Cu는 TiN기판보다는 Ti기판상에서 핵생성이 더 잘 되므로 플라즈마 전처리는 Cu의 핵생성을 돕는 효과를 가져온다.

• 한국진공학회지
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• 제14권4호
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• pp.222-228
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• 2005

2단계 성장법으로 c-plane 사파이어 단결정 기판 위에 metalorganic chemical vapor deposition(MOCVD)법으로 undoped GaN 에피층을 성장시켰다. 고온 성장시 성장 온도 변화가 undoped GaN 에피층의 표면형상과 거칠기, 구조적 결정성, 광학적 성질, 전기적 성질에 미치는 영향을 연구하였다. 수평형 MOCVD 장치를 이용해 압력 300 Torr 저압에서 성장시켰으며, 저온 핵생성층 성장조건은 $500^{\circ}C$로 고정시키고, 2단계 성장 온도를 $850\~1050^{\circ}C$범위로 변화시켰다. 형성된 undoped GaN 에피층을 원자력현미경, 고분해능 X-선회절장치, 광발광측정, 홀 효과 측정 장치 등을 이용하여 분석, 고찰하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.208-208
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• 2012

최근 환경문제가 많이 제기되면서 친환경적 운송수단인 자전거 개발과 관련하여 다양한 기술개발이 이루어지고 있다. 그 중 고부가가치의 서스펜션 포크의 프레임에 고기능성 표면처리로 Arc ion plating deposition system (AIPDS)을 이용하여 부식, 내마모 특성이 뛰어난 TiN 박막을 증착시켰다. AIPDS는 기존의 arc system과 달리 다원계 소재 코팅 공정조건 확립을 위하여 chamber wall에 2개의 rectangular type sputter source를 장착하고 소재의 pre-treatment 용 linear type ion source를 설치하였다. 장비의 Chamber 중앙에는 pipe형 arc cathode를 설치하였으며, 그 주위를 anode 역할을 하는 copper 코일로 감아 이는 발생한 arc를 target인 cathode 축을 중심으로 방향성을 가지고 회전하여 진행 할 수 있도록 유도 하였다. 이 시스템에서 증착된 TiN 박막은 bias 전압 변화에 따른 박막의 구조 및 물성을 평가하였다. XRD 장비를 통하여 TiN 박막의 상분석을 진행하였고, 마모테스터, 원자현미경, 마이크로 비커스 경도기 등을 이용하여 기계적 특성을 평가하였다.

• 마이크로전자및패키징학회지
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• 제8권1호
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• pp.39-43
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• 2001

$SiC_{x}N$_{y}$ film is deposited by electron cyclotron resonance plasma chemical vapor deposition system using $SiH_4$(5% in Ar), $CH_4$ and $N_2$. Ternary phase $SiC_{x}N$_{y}$ thin film deposited at the microwave power of 600 W and substrate temperature of 700 contains considerable amount of strong C-N bonds. Change in $CH_4$flow rate can effectively control the residual film stress, and typical surface roughness of 34.6 (rms) was obtained. Extreme]y high hardness (3952 Hv) and optical transmittance (95% at 633 nm) was achieved, which is suitable for a LIGA mask membrane application.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.509-512
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• 2001

Aluminum nitride(AlN) thin films were deposited on silicon substrates using RF magnetron sputtering at various deposition conditions and investigated the characteristics. It was used XRD, AES, SEM, and HP-4145B semiconductor parameter analyzer to analysis deposited AlN thin films. The deposition conditions for the good c-axis orientation were 100 W of RF power, $200^{\circ}C$ of substrate temperature and 15 mTorr of working pressure. The leakage current density was less then $1.3{\times}10^{-7}A/cm^{2}$. And it was also investigated the etching properties of deposited AlN thin films for application.

• 센서학회지
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• 제16권4호
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• pp.301-306
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• 2007

AlN thin film for SAW filter application was deposited on (100) silicon wafers by reactive magnetron sputtering method. The structural characteristics were dependent on the deposition conditions such as sputtering pressure, RF power, substrate temperature, and nitrogen partial pressure. Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Electron Probe MicroAnalyzer (EPMA) and Atomic Force Microscope (AFM) have been used to find out structural properties and preferred orientation of AlN thin films. Insertion loss of SAW devices was 28.51 dB and out of band rejection was about 24 dB.