• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.135.3-135
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• 1998

• 센서학회지
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• 제5권3호
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• pp.87-92
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• 1996

Pb과잉인 PLT 타겟을 이용하여 MgO(100) 단결정 기판위에 고주파 마그네트론 스펏터링법으로 PLT박막을 제조하였으며, c-축 배향에 따른 물리적 및 전기적 특성을 조사하였다. PLT박막의 c-축 배향성은 제조조건에 따라 변화하며, 본 연구에서의 제조조건은 기판온도가 $640^{\circ}C$, 분위기압이 10 mTorr, $Ar/O_{2}$비가 10 및 고주파 전력밀도가 $1.7 W/cm^{2}$이었다. 이러한 조건에서 제조된 PLT 박막은 표면에서의 Pb/Ti 비가 1/2, 저항률이 $8{\times}10^{11}{\Omega}{\cdot}cm$ 및 비유전률이 110 이었다. PLT박막을 이용하여 초전형 적외선 센서를 제조하였으며, 제조된 적외선 센서의 피크 대 피크 전압은 450 mV, 신호대 잡음비는 7.2 였다.

• 센서학회지
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• 제6권5호
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• pp.423-429
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• 1997

PLT 절연막을 평판표시소자의 재료로 사용하고자 ITO 기판위에 제조하여 그 특성을 조사하였으며 이를 전계 발광소자의 절연층으로 사용하여 그 응용가능성을 조사하였다. PLT 절연막은 기판온도 $500^{\circ}C$, 분위기압 30mTorr에서 증착한 경우 비유전율과 전계파괴강도가 각각 120 및 3.2MV/cm였으며, 성능지수인 $E_{BC}{\cdot}{\epsilon}_r$값이 384로 가장 높았다. 전기저항율은 $2.0{\times}10^{12}{\Omega}{\cdot}cm$ 였다. 또한 증착시 기판온도 및 분위기압에 따른 결정성장을 조사한 결과 기판온도가 $400^{\circ}C$로 낯을 경우에는 비정질 상태였으나 $450^{\circ}C$ 이상의 온도에서는 perovskite와 pyrochlore 구조의 다정질상태의 결정이 성장하였고, 분위기압이 높을수록 결정성장이 더 잘 되었다. 이 PLT 절연막과 ZnS:Mn 형광막을 이용하여 ITO/PLT/ZnS:Mn/PLT/Al 구조의 박막 EL소자를 제작한 결과 문턱전압은 $35.2V_{rms}$였으며, $50V_{rms}$ 1kHz의 구동조건에서 EL의 휘도는 $2400cd/m^{2}$이었으며, 본 실험에서 제조된 박막 EL소자의 최대 발광효율은 0.811m/W였다.

• E2M - 전기 전자와 첨단 소재
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• 제11권10호
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• pp.53-59
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• 1998

Paraelectric lead landthanum titanate(PLT) thin films have been prepared by a reactive dc magnetron sputtering system using a multicomponent metal target. The surface area control of each element on the target markedly facilitates the fabrication of thin films of complex ceramic compounds. A postdeposition heat-treatment was applied to all as-deposited PLT thin films at annealing temperatures up to 75$0^{\circ}C$ for crystalization. The composition of the PLT(28) thin filmannealed at $650^{\circ}C$ was: Pb, 0.73; La, 0.28; Ti, 0.88; O, 2.9. The dielectric constant and dissipation factor of the thin film(200 nm) at low filed measurements (500 Vcm-1) are 1216 and 0.018, respectively. The charge storage density using a typical Sawyer-Tower circuit with a 500 Hz sine wave was 12.5 $\mu$Ccm-2 at the electric field of 200 kVcm-1.

• 한국전기전자재료학회논문지
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• 제16권3호
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• pp.190-194
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• 2003

Dielectric thin films of (P $b_{0.72}$,L $a_{0.28}$) $Ti_{0.93}$ $O_3$ (PLT(28)) have been deposited on Pt(111)/Ti/ $SiO_2$/Si(100) substrates in-situ by pulsed laser deposition using different annealing and deposition Processes. We have investigated the effect of hydrogen annealing on the ferroelectric properties of PLT thin films and found that the annealing process causes the diffusion of hydrogen into the ferroelectric film resulting in the destruction of polarization. We have tried to form the film by a two-step deposition process In order to improve electrical property. Two-step process to grow PLT films was adopted and verified to be useful to enlarge the grain size of the film and to reduce the leakage current characteristics. Structural properties and electrical properties including dielectric constant, ferroelectric characteristics, and leakage current of PLT thin films were shown to be strongly influenced by grain size. The film deposited by using two-step Process including pre-annealing treatment has a strongly(111) orientation. However, the films deposited by using single -step process with hydrogen annealing process show the smallest grain size. The film deposited by using two-step process including pre-annealing treatment shows the leakage current density of below 10$^{-7}$ A/c $m^2$ for the field of smaller than 100 kV/cm. However, the films deposited by using single-step process with hydrogen annealing process and pre-annealing process show worse leakage current density than the film deposited by using two-step process including pre-annealing treatment.tment.

• 한국전기전자재료학회논문지
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• 제11권2호
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• pp.133-137
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• 1998

$(Pb_{0.72}La_{0.28})Ti_{0.93}O_3(PLT(28))$ thin films were fabricated by pulsed laser deposition. PLT films deposited on $Pt/Ti/SiO_2/Si$ at $600^{\circ}C$ had a preferred orientation in (111) plane and at $550^{\circ}C$ had a (100) preferred orientation. We found that (111) preferred oriented films had well grown normal to substrate surface. This PLT(28) thin films of $1{\mu}m$ thickness had dielectric properties of ${\varepsilon}_r$=1300, dielectric $loss{\fallingdotseq}0.03 $. and had charge storage density of 10 [${\mu}C/cm^2$] and leakage current density of less than $10^{-6}[A/cm^2]$ at 100[kV/cm]. These results indicated that the PLT(28) thin films fabricated by pulsed laser deposition are suitable for DRAM capacitor application.

• 한국전기전자재료학회논문지
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• 제18권2호
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• pp.105-108
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• 2005

The Pb(Zr,Ti)O$_3$ thin films were fabricated with Pb(La,Ti)O$_3$ buffers in-situ onto Pt/Ti/SiO$_2$/Si substrates by pulsed laser deposition method. We have observed the increase of the remanent polarization using PLT buffers. The remanent polarization value of 33.4 $\mu$C/$\textrm{cm}^2$ and the coercive field value of 66.4 kV/cm were obtained when the PLT tufter was deposited for 15 seconds. Enhancement of the polarization is resulted from the enhanced orientation of PZT thin film because of the PLT buffet layer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.170-173
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• 2001

Thin films of phase-pure perovskite (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) were deposited in-situ onto Pt/Ti/ $SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. Two-step process to grow (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Electrical properties including dielectric constant, ferroelectric characteristics, crystallization and leakage current of PLT thin films were shown to be strongly inf1uenced by grain size. Also PLT thin films on p-type(100) Si substrate will be fabricated by pulsed laser deposition technique using a Nd:YAG laser with different wavelengths of 355, 532 and 1064 nm. Effect of the variation of laser wavelength on dielectric properties will be discussed. Microstructural and electrical properties of the film were investigated by C-V measurement leakage current measurement and SEM.ent and SEM.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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• pp.416-418
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• 2000

Thin films of phase-pure perovskite $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) were deposited in-situ onto Pt/Ti/$SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Microstructural and electrical properties of the film were investigated by C-V measurement, leakage current measurement and SEM. Two-step process to grow $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1309-1311
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• 1998

$Pb_{1-x}La_xTi_{1-x/4}O_3$ (PLT(x)) thin film has been regarded as one of the most promising materials for applications of sensor, optic devices, and memory devices, because it exhibits various properties as changing the amount of Lanthanum component. So we have prepared PLT thin films on platinized silicon (actually Pt/Ti/$SiO_2$/Si) substrates in oxygen ambient by laser ablation. Energy dispersive X-ray (EDX) revealed that the stoichiometric thin films were fabricated.