• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.12-15
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• 2004

There are two major approaches to obtain texture template for HTS coated conductor (CC) ---IBAD and RABiTS. CC's with IBAD template showed both longer and higher Ic results so far. IBAD for CC began with YSZ, the processing of which is very slow compared to other processings needed for the fabrication of CC. Because of this very slow processing speed, IBAD with other materials such as Gd$_2$Zr$_2$O$_{7}$(GZO) and MgO have been developed. The processings of IBAD-GZO and IBAD-MgO are known to be up to 3times and 100 times. respectively, as fast as the processing of IBAD-YSZ. IBAD-MgO is very attractive in that the processing is very fast. IBAD-MgO also needs additional buffer layer(s). Many materials are being investigated to be used as a buffer layer on top of the MgO. BaZrO$_3$ (BZO) is a good candidate as the buffer layer on top of the IBAD-MgO because it is chemically stable and does not react with YBCO at high temperatures. It also has good lattice match with MgO. The BZO film has been deposited on single crystal MgO, and YBCO film was deposited on BZO/MgO to investigate the possibility of using BZO as both the buffer and capping layer of the CC.C.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.82-85
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• 2002

In recent years, the tantalum nitride(TaN) thin-film has been developed for the electronic resistor and capacitor. In this papers, this study presents the surface profile and sheet-resistance property relationship of reactive-sputtered TaN thin film resistor processed by buffer of Ti and Cr on alumina substrate. The TCR properties of the TaN films were discussed in terms of reactive gas ratio, ratio of nitrogen, crystallization and thin films surface morphology due to annealing temperature. It is clear that the TaN thin-films resistor electrical properties are low TCR related with it's buffer layer condition. Ti buffer layer thin film resistor having a good thermal stability and lower TCR properties then Cr buffer expected for the application to the dielectric material of passive component.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.207-210
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• 2005

In order to investigate the influence of the homo buffer layer on the microstructure of the ZnO thin film, undoped ZnO buffer layer were deposited on sapphire (0001) substrates by ultra high vaccum pulsed laser deposition (UHV-PLD) and molecular beam eiptaxy (MBE). After high temperature annealing at $600^{\circ}C$ for 30min, undoped ZnO buffer layer was deposited with various oxygen pressure (35~350mtorr). On the grown layer of undoped ZnO, Arsenic-doped(l, 3wt%) ZnO layers were deposited by UHV-PLD. The optical property of the ZnO was analyzed by the photoluminescence (PL) measurement. From $\Theta-2\Theta$ XRD analysis, all the films showed strong (0002) diffraction peak, and this indicates that the grains grew uniformly with the c-axis perpendicular to the substrate surface. Field emission scanning electron microscope (FE-SEM) revealed that microstructures of the ZnO were varied with oxygen pressure, arsenic doping level, and the deposition method of undoped ZnO buffer layers. The films became denser and smoother in the cases of introducing MBE-buffer layer and lower oxygen pressure during As-doped ZnO deposition. Higher As-doping concentration enhanced the columnar-character of the films.

• 한국초전도ㆍ저온공학회논문지
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• 제9권3호
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• pp.5-8
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• 2007

All three buffer layers of $Y_2O_3$, YSZ, and $CeO_2$ have been deposited on the biaxially textured metal substrates using rf-sputtering method, The first 50-70nm thick $Y_2O_3$ films were grown epitaxially on biaxially textured metal substrates as a seed layer and followed by the diffusion barrier ${\sim}100nm$ thick YSZ and subsequent capping layer ${\sim}200nm$ thick $CeO_2$ deposited epitaxially on top of $Y_2O_3$ seed layer. The epitaxial orientation of all three layers were all (100) grown with rocking curve Full Width at Half Maximum(FWHM) of $4-5^{\circ}$ and in plane phi-scan FWHM of $6-8^{\circ}$ using X -ray diffraction analysis. The NiO phases formed during the $Y_2O_3$ seed layer deposition seem to degrade the crystallinity and roughen the surface morphology of the following layer observed by AFM(Atomic Force Microscopy). The buffered tapes were used as substrates for long length YBCO coated conductors with high critical current density $J_c$. The five multi-turn of metal tapes was employed to increase the thickness of films and production rate to compensate the low growth rate of rf-sputtering method.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.162-163
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• 2013

Single-crystal InGaZnO (IGZO) thin films were spontaneously formed as periodic layered structure along the c-axis by thermal treatment at high temperature. when the IGZO superlattice were synthesized by sol-gel method, the effects of preferred growth orientations and the flatness of ZnO buffer layer were investigated. $InGaO_3(ZnO)_2$ superlattice were favorably formed on ZnO buffer layer with single preferred orientation. Futhermore, it showed relatively high Seebeck coefficient and power factor.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.54-56
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• 2005

Fabrication of c-axis oriented $(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ thick fabricated has been attempted using Ni substrates with the buffer layer of Cr or NiO. Coexistence of $(Hg_{0.75}Rc_{0.25})Ba_2Ca_3Cu_4O_y$ pellets wad found to stabilize $(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ phase of the tape. The c-axis oriented tapes were reproducibly obtained on the NiO/Ni substerate and they recorded high $B_{irr}$ at 77K.$(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ 1223.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.148-151
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• 1995

Excimer laser has been used to fabricate superconducting YBa$_2$Cu$_3$O$\sub$7-x/(YBCO) thin films on various substrates. An XeCl excimer laser with an wavelength of 308 nm was used to deposit both buffer layer and superconducting thin film on sapphire substrate. The characterizations of the interface between thin film and substrate were performed. The interfacial properties of thin films on buffered sapphire and on bare sapphire were compared. With a 20 nm PrBa$_2$Cu$_3$O$\sub$7-x/(PBCO) buffer layer, no diffusion layer was observed between film and substrate while the diffusion layer with about 30 nm thickness was observed between film and sapphire without buffer layer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.186-189
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• 2003

The MFIS capacitors were fabricated using a metalorganic decomposition method. Thin layers of $ZrO_2$ and $CeO_2$ were deposited as a buffer layer on Si substrate and BLT thin films were used as a ferroelectric layer. The electrical and structural properties of the MFIS structure were investigated. X -ray diffraction was used to determine the phase of the BLT thin films and the quality of the $ZrO_2$ and $CeO_2$ layer. AES show no interdiffusion and the formation of amorphous $SiO_2$ layer is suppressed by using the $ZrO_2$ and $CeO_2$ film as buffer layer between the BLT film and Si substrate. The width of the memory window in the C-V curves for the $BLT/ZrO_2/Si$ and $BLT/CeO_2/Si$ structure is 2.94 V and 1.3V, respectively. The experimental results show that the BLT-based MFIS structure is suitable for non-volatile memory FETs with large memory window.

• 한국초전도ㆍ저온공학회논문지
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• 제6권3호
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• pp.27-32
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• 2004

High temperature superconducting coated conductor has a structure of /< superconducting layer>//. The buffer layer consists of multi layer, and the architecture most widely used in RABiTS approach is CeO$_2$(cap layer)/YSZ(diffusion barrier layer)/CeO$_2$(seed layer). Evaporation technique is used for the CeO$_2$ layer and DC reactive sputtering technique is used for the YSZ layer, A chamber was set up specially for DC reactive sputtering, Detailed features are as following. A separator divided the chamber into two halves a sputtering chamber and a reaction chamber. The argon gas for sputtering target elements flows out of the cap of sputtering gun, and water vapor for reaction with depositing species spouts near the substrate. Turbo pump is connected with reaction chamber. High speed deposition of YSZ film could be achieved in the chamber. Detailed deposition conditions (temperature and partial pressure of reaction gas) were investigated for the rapid growth of high quality YSZ film.

• Transactions on Electrical and Electronic Materials
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• 제10권1호
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• pp.24-27
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• 2009

N-doped ZnO thin films were deposited on n-type Si(100) and homo-buffer layer, and undoped ZnO thin film was also deposited on homo-buffer layer by RF magnetron sputtering method. After deposition, all films were in-situ annealed at $800^{\circ}C$ for 5 minutes in ambient of $O_2$ with pressure of 10Torr. X -ray diffraction shows that the homo-buffer layer is beneficial to the crystalline of N-doped ZnO thin films and all films have preferable c-axis orientation. Atomic force microscopy shows that undoped ZnO thin film grown on homo-buffer layer has an evident improvement of smoothness compared with N-dope ZnO thin films. Hall-effect measurements show that all ZnO films annealed at $800^{\circ}C$ possess p-type conductivities. The undoped ZnO film has the highest carrier concentration of $1.145{\times}10^{17}cm{-3}$. The photoluminescence spectra show the emissions related to FE, DAP and many defects such as $V_{Zn}$, $Zn_O$, $O_i$ and $O_{Zn}$. The p-type defects ($O_i$, $V_{Zn}$, and $O_{Zn}$) are dominant. The undoped ZnO thin film has a better p-type conductivity compared with N-doped ZnO thin film.