• 한국재료학회:학술대회논문집
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• 한국재료학회 2002년도 추계학술발표강연 및 논문개요집
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• pp.95-95
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• 2002

• 한국세라믹학회지
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• 제40권1호
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• pp.46-51
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• 2003

Liquid delivery MOCVD 공정으로 200nm 정도의 두께를 가진 강유전성 S $r_{0.7}$B $i_{2.1}$T $a_{2.0}$ $O_{9}$ 박막을 Pt/Ti/ $SiO_2$/Si 기판 위에 증착하였다. 본 실험에서는 Sr(TMHD)$_2$.pmdeta, Bi(ph)$_3$ 그리고 Ta( $O^{i}$ Pr)$_4$(TMHD)를 출발 물질로 사용하였으며 n-butyl acetate와 pentamethyldiethylenetriamine를 용매로 사용하였다. 이 실험의 기판 온도와 압력 조건은 각각 57$0^{\circ}C$와 5 Torr였다. 78$0^{\circ}C$에서 열처리한 SBT 박막의 3V와 5V 인가 전압하에서의 잔류분극값은 각각 7.247 $\mu$C/$\textrm{cm}^2$와 8.485 $\mu$C/$\textrm{cm}^2$이었다.다.다.

• 한국결정성장학회지
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• 제9권1호
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• pp.34-38
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• 1999

유기금속 화학 증착법(MOCVD)을 이용하여 Si(100) 기판 위에 $TiO_2$와 PbO의 동시 증착으로 $Pb(TMHD)_2$(PT) 박막을 증착하였다. 원료물질로는 Titanium tetra-isopropoxide(TTIP)와 $Pb(TMHD)_2$를 사용하였다. 증착온도를 $520^{\circ}C$, Pbdbfid을 30 sccm으로 고정하고, 전체유량을 750 sccm으로 하여 TTIP의 증발온도와 유량에 따른 PT 박막의 XRD 변화를 관찰하였다. PT 박막 생성은 TTIP의 증발온도 및 유량이 각각 48~$50^{\circ}C$와 18~22sccm 영역에서 생성되었으며, 생성된 박막과 기판의 계면에서는 Pb, Si, O의 상호확산을 관찰할 수 있었다.

• 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.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.16-20
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• 2004

YB $a_2$C $u_3$$O_{7-x}$ (YBCO) films were deposited on (100) SrTi $O_3$ single crystal substrates by a metal organic chemical vapor deposition (MOCVD) system of hot-wall type using single liquid source. Under the condition of the mole ratio of Y(tmhd)$_3$:Ba(tmhd)$_2$:Cu(tmhd)$_2$= 1:2.1:2.9. the deposition pressure of 10 Torr. the MO source line speed of 15 cm/min. the Ar/ $O_2$ flow rate of 800/800 sccm. YBCO films were prepared at the deposition temperatures of 780∼89$0^{\circ}C$. In case of the YBCO films with 2.2 ${\mu}{\textrm}{m}$ thickness deposited for 6 minutes at 86$0^{\circ}C$. XRD pattern showed complete c-axis growth and SEM morphology showed dense and crack-free surface. The atomic ratios of Ba/Y and Cu/Ba in the film were 1.92 and 1.56. respectively. The deposition rate of the film was as high as 0.37 ${\mu}{\textrm}{m}$/min. The critical temperature ( $T_{c.zero}$) of the film was 87K. The critical current of the film was 104 A/cm-width. and the critical current density was 0.47 MA/$\textrm{cm}^2$. For the thinner film of 1.3 ${\mu}{\textrm}{m}$ thickness. the critical current density of 0.62 MA/$\textrm{cm}^2$ was obtained.d.

• 한국재료학회지
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• 제9권3호
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• pp.234-239
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• 1999

PECVD(Plasma enhanced chemical vapor deposition)을 이용하여 yttria-stabilized zirconia(YSZ) 박막을 제조하였다. 반응물질로 금속유기화합물을 $Zr[TMHD]_4$와 $Y[TMHD]_3$그리고 산소를 사용하였으며, 증착온도는 $425^{\circ}C$, rf power는 0~100W까지 적용하였다. YSZ 박막은 (200)면이 기판에 평행한 입벙정상 구조를 가졌으며, 1시간 내에 $1\mu\textrm{m}$ 두께를 형성하였다. EDX에 의한 막의 성분분석 결과로부터 환산된 박막내의 $Y_2O_3$의 함량은 0-36%의 범위였다. 버블러의 온도 및 운반기체의 유량이 증가함에 따라 박막의 두께 역시 비례하여 증가하였는데, 이는 precursor의 flux 증가로 인한 박막내의 $Y_2O_3$의 함량증가에 의한 것이었다. Zr 및 Y, O는 박막의 두께에 따라 일정한 조성비를 나타내었다. 운반기체를 Ar로 하였을 때 $1000\AA$이하의 크기를 갖는 YSZ 입자들이 column 모양으로 기판에 수직하게 성장하였으며, 운반기체가 He인 경우에도 column 모양으로 성장하였으며 입도가 $1000~2000\AA$으로 Ar의 경우보다 조대해졌다. XRD 분석결과 $Y_2O_3$의 함량이 증가함에 따라 YSZ의 격자상수 값이 약간씩 증가하였다. 이는 박막 전반에 걸쳐 형성된 균열에 의해 격자변형으로 인해 발생한 응력을 완화시켰지 때문이다.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2006년도 추계학술대회 발표 논문집
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• pp.166-169
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• 2006

A promising capacitor, which has conformable step coverage and good uniformity of thickness and composition, is needed to manufacture high-density non-volatile FeRAM capacitors with a stacked cell structure. In this study, ferroelectric $Bi_{3.61}Nd_{0.39}Ti_3O_{12}$ (BNT) thin films were prepared on $Pt(111)/Ti/SiO_2/Si$ substrates by the liquid delivery system MOCVD method. In these experiments, $Bi(ph)_3$, $Nd(TMHD)_3$ and $Ti(O^iPr)_2(TMHD)_2$ were used as the precursors and were dissolved in n-butyl acetate. The BNT thin films were deposited at a substrate temperature and reactor pressure of approximately $600^{\circ}C$ and 4.8 Torr, respectively. The microstructure of the layered perovskite phase was observed by XRD and SEM. The remanent polarization value (2Pr) of the BNT thin film was $31.67\;{\mu}C/cm^2$ at an applied voltage of 5 V.

• 한국세라믹학회지
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• 제42권4호
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• pp.219-223
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• 2005

A promising capacitor, which has conformable step coverage and good uniformity of thickness and composition, is needed to manufacture high-density non-volatile FeRAM capacitors with a stacked cell structure. In this study, ferroelectric $Bi_{3.61}Nd_{0.39}Ti_3O_{12}$ (BNdT) thin films were prepared on $Pt(111)/TiO_2/SiO_2/Si$ substrates by the liquid delivery system MOCVD method. In these experiments, $Bi(ph)_{3}$, $Nd(TMHD)\_{3}$ and $Ti(O^iPr)_{2}(TMHD)_{2}$ were used as the precursors and were dissolved in n-butyl acetate. The BNdT thin films were deposited at a substrate temperature and reactor pressure of approximately $600^{\circ}C$ and 4.8 Torr, respectively. The microstructure of the layered perovskite phase was observed by XRD and SEM. The remanent polarization value (2Pr) of the BNdT thin film was $31.67\;{\mu}C/cm^{2}$ at an applied voltage of 5 V.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.21-22
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• 2002

• Progress in Superconductivity
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• 제7권1호
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• pp.69-76
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• 2005

Complex single buffer composed of yttrium and samarium oxide was deposited on the metallic substrates by MOCVD (metal organic chemical vapor deposition) method using single liquid source. Two different types of the substrates with in-plane textures of about $8{\sim}10$ degree of Ni and $3at.\%W-Ni$ alloy were used. Y(tmhd: 2,2,6,6-tetramethyl-3,5-heptane dionate)$_3$:Sm(tmhd)$_3$ of liquid source was adjusted to 0.4:0.6 to minimize the lattice mismatch between the complex single buffer and the YBCO. The epitaxial growth of $(Y_{x}Sm_{1-x})_{2}O_3$ was achieved at the temperature higher than $500^{\circ}C$ in $O_2$ atmosphere. However, it was found that the formation of NiO accelerated with increasing deposition temperature. By supplying $H_{2}O$ vapor, this oxidation of the substrate could be suppressed throughout the deposition temperatures. We could get the epitaxial growth on pure Ni substrate without the formation of NiO. The competitive (222) and (400) growths were observed at the deposition temperatures of $650\~750^{\circ}C$, but the (400) growth became dominant above $800^{\circ}C$. The $(Y_{x}Sm_{1-x})_{2}O_3$-buffered metallic substrates can be used as the buffer for YBCO coated conductor.