• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.7
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• pp.1491-1496
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• 2005

We fabricated the $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of $100\%$ perovskite phase by drying at $350^{\circ}C$ after each coating and final annealing at $650^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the $Pt/Ti/SiO_2/Si$ substrate and its dielectric constant and leakage current density were measured as 936 and $1.1{\mu}A/cm^2$, respectively.

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.243-246
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• 2006

The LiCoO2 thin films were prepared on the Pt/Ti/SiO2/Si substrate by spin coating using citrate sol. The citrate sol was spin-coated on substrate and dried at 380oC for 15 min. to evaporate the solvents and remove the organic materials. The as-deposited films were annealed at 750oC for 10 min. in air for crystallization. The X-ray diffraction patterns for the film have been indexed hexagonal system with space group R3m. The active area of LiCoO2 films for electrochemical test was about 11cm2. A Li foil and 1M LiClO4 in propylene carbonate(PC) and ethylene carbonate(EC) (1:1)were used as an anode and an electrolyte, respectively. The galvanostatic charge-discharge test was carried out at constant current density ranging from 5 A/cm2 in the voltage window between 4.2 and 3.0 V. The first discharge capacity of the film is 0.35Ah/cm2-m. The cycling behavior of the LiCoO2 film is also reported.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.865-868
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• 2005

We fabricated the $Pb_{0.72}La_{0.28}TiO_3 (PLT(28))$ thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of 100% perovskite phase by drying at 350$^{\circ}C$ after each coating and final annealing at 650$^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the Pt/Ti/SiO$_2$/Si substrate and its dielectric constant and leakage current density were measured as 936 and 1.1${\mu}$A/cm$^2$, respectively

• Journal of Sensor Science and Technology
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• v.7 no.5
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• pp.372-376
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• 1998

We developed a pulsed laser deposition(PLD) apparatus for depositing various thin films. In this study, the formation of $NbS_2$ thin film was performed in the vacuum chamber by PLD method. $Al_2O_3$(012) and Si(111) were used as the substrates. In order to investigate the growth conditions of a high crystalline $NbS_2$ thin film, the S/Nb composition ratio was varied from 2.0 to 5.25 and the substrate temperature was varied from the room temperature to $600^{\circ}C$. From the result of X-ray diffraction studies of the prepared $NbS_2$ thin films, it was reported that the $NbS_2$, thin film showed a good crystallinity at substrate temperature $600^{\circ}C$ and with S/Nb composition ratio 4.0 on $Al_2O_3$(012) but did not on Si(111). The films exhibited c-axis orientation.

• Journal of the Korean Vacuum Society
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• v.8 no.3B
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• pp.322-326
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• 1999

We have investigated the growing process of a silicon film on the $CeO_2/Si$ surface. The silicon was deposited by using electron beam deposition method. The $CeO_2$(111) film was grown on a (111)-oriented silicon substrate at $700^{\circ}C$ at oxygen [partial pressure of $5\times10^{-5}$ Torr. To investigate the condition of epitaxial growth of si films on the $CeO_2/Si$ substrate, we deposited Si at various temperature니 The overlayer silicon was characterized by using x-ray diffraction(XRD). double crystal x-ray diffraction (DCXRD), and transmission electron microscopy (TEM). At temperature higher than $690^{\circ}C$, $CeO_2$ layer was observed at the $CeO_2/Si$ interface, which was formed by chemical reaction with silicon and oxygen dissociated from $CeO_2$. When silicon was deposited on the $CeO_2/Si$ at $620^{\circ}C$, silicon grew epitaxially along the (111)-direction.

• Korean Journal of Materials Research
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• v.12 no.1
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• pp.94-99
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• 2002

The electrical properties of porous $SiO_2/ITO$ nano thin film were studied by complex impedance and conductive mechanisms were analyzed. According to the results of complex impedance, the activation energy of $SiO_2/ITO$ and $Zn-SiO_2/ITO$ were 0.309 eV, 0.077 eV in below $450^{\circ}C$ and 0.147 eV in over $450^{\circ}C$, respectively. In case of $SiO_2/ ITO$, slightly direct tunneling occurred at room temperature. The contribution for conduction was very tiny because of high barrier of silica. However, the conductivity abruptly increased in over $300^{\circ}C$ by Thermally assisted tunneling. In case of $Zn-SiO_2/ITO$, high conductivity in 1.26 ${\Omega}^{ -1}{cdot}cm^{-1}$ at room temperature appeared by space charge conduction or Frenkel-poole emission that Zn ions play a role as localized electron states.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.132-136
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• 2009

SiOC thin film of hybrid-type that is the limelight as low dielectric material of next generation were deposited by plasma enhanced chemical vapor deposition (PECVD) method with bistrimethylsilylmethane (BTMSM) precursor increased by 2 sccms from 24 sccms to 32 sccm. Manufactured samples are analyzed components by measuring FT/IR absorption lines. It is a tendency that seems to be growing of Si-O-Si(C) bonding group and narrowing of Si-O-$CH_3$ bonding group relative to the increasing flow-rate BTMSM. The chemical shift in the XPS analysis was shown in the specimens between the BTMSM=26 sccm and BTMSM = 28 sccm. The binding energy of Si 2p, C 1s and O 1s electron orbit spectra was the low-est at the specimen of the BTMSM=26 sccm. From the results of electrical Properties using the 1 MHz C - V measurements, the dielectric constant was 2.32 at the specimen with the BTMSM = 26 sccm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.4
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• pp.327-329
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• 2005

Pb(Zr/sub 0.52/Ti/sub 0.48/)O₃(PZT) thin films were deposited by using a pulsed laser deposition method on a Pt/Ti/SiO₂/Si substrate with (Pb/sub 0.72/La/sub 0.28/)Ti/sub 0.93/O₃ (PLT) buffer and on a Pt/Ti/SiO₂/Si substrate without buffer. These films were annealed in H₂-contained ambient for 30 minutes at the substrate temperature of 400。C to evaluate the forming gas annealing effects. The comparative studies on the ferroelectric properties of these two films were carried out, which are shown that ferroelectric properties, such as remanent polarization didn't change in the case of PLT buffered PZT film while remanent polarization value of PZT film degraded from 20.8 C/㎠ to 7.3 C/㎠. The leakage current became higher in both cases, but that of the more-oriented PZT film had the moderate value of the 10/sup -6/ order of A/㎠. This is mainly because the hydrogen atoms which make the degradation of PZT films cannot infiltrate into the more -oriented PZT film as well as the less-oriented PZT film.

• Journal of the Korean Ceramic Society
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• v.30 no.9
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• pp.695-700
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• 1993

In this study, we prepared Pb-Ti stock solution by sol-gel processing and deposited PbTiO3 thin film on a Pt coated SiO2/Si wafer by spin coating using the stock solution. We used lead acetate trihydrate and titanium isopropoxide. The stock solution was partially hydrolized and finally a 0.25M coating solution was prepared. We achieved spin coating at 4000rpm for 30 seconds and heated the thin film at 375$^{\circ}C$ for 5 minutes and at $600^{\circ}C$ for 5 minutes successively, first and second heating state. And the thin film was finally sintered at 90$0^{\circ}C$ for 1 hour in the air. The upper electrode of the thin film was made by gold sputtering and was cricle shape with radius 0.4mm. Measured dielectric constant, dissipation factor and phase transition temperature(Cuire Temp.) were about 275, 0.02 and 521$^{\circ}C$ respectively. To observe ferroelectric characteristics we calculated Pr(remnant polarization) and Ec(coercive field) byhysteresis curve. Ec was 72kV/cm and Pr was 11.46$\mu$C/$\textrm{cm}^2$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.125-129
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• 2004

[ $BaTi_4O_9$ ] thin film were grown on $Pt/Ti/SiO_2/Si$ substrate using rf magnetron sputter, and the microstructure and dielectric properties of the thin films were investigated. For the film grown at $350^{\circ}C$ and rapidly thermal annealed at $900^{\circ}C$, the $BaTi_5O_{11}$ Phase was formed. However, the $BaTi_4O_9$ phase was formed when the growing temperature exceeded $450^{\circ}C$ The dielectric constant of the $BaTi_4O_9$ thin film grown at $550^{\circ}C$ and rapidly thermal annealed at $900^{\circ}C$ was about 40 at low frequency range($100kHz{\sim}1MHz$) and 36 at microwave range($1{\sim}10GHz$) which is very close to that of the bulk $BaTi_4O_9$ phase. The dissipation factor was very low, about 0.005 at low frequency as well as microwave range.