• 한국세라믹학회지
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• 제48권1호
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• pp.69-73
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• 2011

A $ZrO_2$ thin film as a corrosion protective layer was deposited on Zircaloy-4 (Z-4) clad material using $N_2O$ as a reactive gas by RF reactive magnetron sputtering at room temperature. The Z-4 substrate was located in plasma or out of plasma during the $ZrO_2$ deposition process to investigate mechanical and corrosive properties for the plasma immersion. Tetragonal and monoclinic phases were existed in $ZrO_2$ thin film immersed in plasma. We observed that a grain size of the $ZrO_2$ thin film immersed in plasma state is larger than that of the $ZrO_2$ thin film out of plasma state. In addition, the corrosive property of the $ZrO_2$ thin films in the plasma was characterized using the weight gains of Z-4 after the corrosion test. Compared with the $ZrO_2$ thin film immersed out of plasma, the weight gains of $ZrO_2$ thin film immersed in plasma were larger. These results indicate that the $ZrO_2$ film with the tetragonal phase in the $ZrO_2$ can protect the Z-4 from corrosive phenomena.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1483-1490
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• 2011

The protection effect of a $ZrO_2$ coating layer on a $LiCoO_2$ thin film was characterized. A wide and smooth $LiCoO_2$ thin film offers sufficient opportunity for careful observation of the reaction at the interface between cathode (coated and uncoated) and electrolyte. The formation of a $ZrO_2$ coating on a $LiCoO_2$ thin film was confirmed by secondary ion mass spectrometry. Scanning electron and atomic force microscopy were used to characterize the surface morphologies of coated and uncoated films before and after cycling. A $ZrO_2$-coated $LiCoO_2$ film showed a higher discharge capacity and rate capability than an uncoated film. This may be associated with a surface protection effect of the coating. The surface of a pristine film was damaged during cycling, whereas the coated film maintained a relatively clear surface under the same measurement conditions. This result clearly demonstrates the protection effect of a $ZrO_2$ coating on a $LiCoO_2$ thin film.

• The Korean Journal of Ceramics
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• 제1권3호
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• pp.143-146
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• 1995

Twins along(202) and (211) planes are observed in monoclinic $ZrO_2$ thin film, which is deposited on Si substrate by MOCVD at $350^{\circ}C$ and annealed at $1150^{\circ}C$ for 10 hours in air. These types of twin have not been reported in monoclinic $ZrO_2$. The twins seem to be originated from the two dimensional tensile stresses applied to the $ZrO_2$ thin film due to the different thermal expansions of $ZrO_2$ thin film and Si substrate.

• 한국전기전자재료학회논문지
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• 제30권4호
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• pp.199-203
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• 2017

$ZrO_2/PSS$ thin film with a high refractive index was fabricated on a glass substrate by a layer-by-layer self-assembly method. The surface morphology and thickness of the fabricated $ZrO_2/PSS$ thin films were measured as a function of the number of $(ZrO_2/PSS)n$. As the number of $(ZrO_2/PSS)n$ increased from n = 5 to n = 20, RMS roughness decreased from 29.01 nm to 8.368 nm. The $ZrO_2$ thin films exhibited high transmittance of 85% or more; and the 15-bilayer thin film exhibited the highest transmittance among the samples. The transmittance of the fabricated $(ZrO_2/PSS)_{15}$ thin film was ca. 90.8% in the visible range. The refractive index of the glass substrate coated by a $(ZrO_2/PSS)_{15}$ thin film with a thickness of 160 nm increased from ca. 1.52 to 1.74 at the 632 nm wavelength.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1240_1241
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• 2009

In this paper, sol-gel-spin coated $Pb(ZrTi)O_3$ thin film with $ZrO_2$ buffer-layer and $PbTiO_3$ seed-layer was investigated for vibration MEMS energy harvester to scavenge power from ambient vibration via d33 piezoelectric mode. Piezoelectric thin film deposition techniques on insulating layer is the important key for $d_{33}$ mode of piezoelectric vibration energy harvester. $ZrO_2$ buff-layer was utilized as an insulating layer. $PbTIO_3$ seed-layer was applied as an inter-layer between PZT and $ZrO_2$ layer to improve the crystalline of PZT thin film. The fabricated PZT thin film had a remanent polarization of 5.3uC/$cm^2$ and the coercive field of 60kV/cm. The fabricated energy harvester using PZT thin film with PTO seed-layer generated 1.1uW of electrical power to $2.2M{\Omega}$ of load with $4.4V_{pvp}$ from vibration of 0.39g at 528Hz.

• 한국재료학회지
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• 제18권4호
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• pp.211-217
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• 2008

A $ZrO_2$ coating solution containing $ZrO_2$ photo-catalysis, which is transparent in visible light, was prepared by the hydrolysis of alkoxide, and thin films on the $SiO_2$ glass substrate were formed in a dipcoating method. These thin films were heat-treated at temperatures ranging from $250^{\circ}C-800^{\circ}C$ and their characteristics were subjected to thermal analysis, XRD, spectrometry, SEM, EDS, contact angle measurement, and AFM. Tetragonal $ZrO_2$ phase was found in the thin film heat treated at $450^{\circ}C$, and anatase $TiO_2$ phase was detected in the thin film heat-treated at $600^{\circ}C$ and above. The thickness of the films was approximately 300 nm, and the roughness was 0.66 nm. Thus, the film properties are excellent. The films are super hydrophilic with a contact angle of $4.0^{\circ}$; moreover, they have self-cleaning effect due to the photo catalytic property of anatase $TiO_2$.

• 산업기술연구
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• 제25권A호
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• pp.157-162
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• 2005

In this study, the fabrication of PZT films was performed from a multilayer structure comprising $TiO_2$, $ZrO_2$ and PbO thin films prepared by rapid themal chemical vapor deposition(RTMOCVD). $TiO_2$, $ZrO_2$ and PbO are the component layers of oxide multilayer system for a single phase PZT thin film. The composition control of PZT thin film was done by the thickness control of individual component layer. The composition ratio of Pb:Ti:Zr with thickness were 1:0.94:0.55. Occurrence of a single-phase of PZT was initiated at around $550^{\circ}C$ and almost completed at $750^{\circ}C$ under the fixed time of 1hr. As the concentration of Pb increased, the roughness and crystallization in the film increased. From the as result of using XPS and TEM, the single phase formation through annealing is evident. The electrical properites of the prepared PZT thin film(Zr/Ti=40/60, 300 nm) on a Pt-coated substrate were as follow: dielectric constant ${\varepsilon}_r=475$, coercive field Ec=320 kV/cm, and remanant polarization $P_r=11{\mu}C/cm^2$ at an applied voltage of 18 V.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2333-2337
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• 2007

Nanoporous TiO2 and ZrO2 thin films were spin-coated using a surfactant-templated approach from Pluronic P123 (EO20PO70EO20) as the templating agent, titanium alkoxide (Ti(OC4H9)4) as the inorganic precursor, and butanol as a the solvent. The control of the electronic structure of TiO2 is crucial for its various applications. We found that the band gap of the hybrid nanoporous thin films can be easily tuned by adding an acetylacetonestabilized Zr(OC4H9)4 precursor to the precursor solution of Ti(OC4H9)4. Pores with a diameter of 5 nm-10 nm were randomly dispersed and partially connected to each other inside the films. TiO2 and ZrO2 thin films have an anatase structure and tetragonal structure, respectively, while the TiO2-ZrO2 hybrid film exhibited no crystallinity. The refractive index was significantly changed by varying the atomic ratio of titanium to zirconium. The band gap for the nanoporous TiO2 was estimated to 3.43 eV and that for the TiO2-ZrO2 hybrid film was 3.61 eV.

• 한국세라믹학회지
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• 제42권9호
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• pp.624-630
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• 2005

To investigate the possibility of the $ZrO_2$ buffer layer as the insulator for the Metal-Ferroelectric-Insulator-semiconductor (MFIS) structure, $ZrO_2$ and $SrBi_2Ta_2O_9$ (SBT) thin films were deposited on the P-type Si(111) wafer by the R.F. magnetron-sputtering method. According to the process with and without the post-annealing of the $ZrO_2$ buffer layer and SBT thin film, the diffusion amount of Sr, Bi, Ta elements show slight difference through the Glow Discharge Spectrometer (GDS) analysis. From X-ray Photoelectron Spectroscopy (XPS) results, we could confirm that the post-annealing process affects the chemical binding condition of the interface between the $ZrO_2$ thin film and the Si substrate. Compared to the MFIS structure without the post-annealing of the $ZrO_2$ buffer layer, memory window value of MFlS structure with post-annealing of the $ZrO_2$ buffer layer were considerably improved. The window memory of the Pt/SBT (260 nm, $800^{\circ}C)/ZrO_2$ (20 nm) structure increases from 0.75 to 2.2 V under the applied voltage of 9 V after post-annealing.

• 한국세라믹학회지
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• 제40권5호
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• pp.475-480
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• 2003

금 미립자를 ZrO$_2$중에 분산시켜 비선형광학재료, 선택흡수막 및 투과막 등 새로운 기능성 재료로 활용하기 위하여 Au/ZrO$_2$나노복합체 박막을 제조하였다. 딥-코팅법에 의해 제조한 박막을 열처리한 후 그 특성을 엑스선 회절분석,분광분석, 주사탐침현미경 및 전자현미경 등을 이용하여 조사하였다. Au/ZrO$_2$ 박막은 150 nm의 두께를 보였으며, 박막의 표면에 분산된 금 미립자의 크기는 15~35 nm였으며, 표면거칠기는 약 1.06 nm로 막질이 우수하였다. 그리고 가시광선 영역인 600~650 nm의 파장범위에서 금 미립자의 플라즈마 공명에 의한 흡수 피_크를 나타내어 비선형광학성을 확인할 수 있었다.