• The Korean Journal of Ceramics
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• v.7 no.2
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• pp.93-96
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• 2001

The Y- or Yb-doped SrZrO$_3$ proton conductors were fabricated using the powders prepared by the self-propagating high-temperature synthesis (SHS). The electrical conductivity was evaluated from an a.c. impedance measurements. The conductivity of SrZr$_{0.92}$Yb$_{0.08}$O$_{3-\delta}$ was 1.8$\times$10$^{-3}$ Scm$^{-1}$ at $900^{\circ}C$ in dry air atmosphere and its activation energy was 0.50 eV. The conductivity in wet air was larger, compared with the dry air, and the activaton energy of SrZr$_{0.92}$Yb$_{0.08}$O$_{3-\delta}$ in wet air was 0.40 eV.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.146-148
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• 2003

SrZrO$_3$ resistive oxide barriers on Ag sheathed Bi2223 monocore tapes were prepared by the sol-gel and dip coating method to reduce AC coupling loss. The performance of the dip-coated SrZrO$_3$ thin films was evaluated in terms of bond strength and surface microstructure by varying the amount of PVP (polyvinylpyrrolidone) binder. Although bond strength and coating thickness increased as the PVP content rose, surface microcracking was more severe for the specimen containing higher content of PVP binder. It suggests that coating thickness and microcracking of the SrZrO$_3$ films on Bi2223 tapes was governed primarily by the amount of PVP binder.

• Journal of the Korean Ceramic Society
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• v.39 no.10
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• pp.1001-1006
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• 2002

Bond strength of $SrZrO_3$ resistive oxide barrier on Ag sheathed Bi(2223) tapes prepared by the sol-gel and dip-coating method was evaluated with an aid of Taguchi method and $L_18(2^1{\times}3^7)$ orthogonal arrays to determine the optimal process combination of levels of factors that best satisfy the bigger is better quality characteristic. The observed optimal condition is as follows: Sr/Zr mol ratio(0.3/0.7), amount of organic vehicle(5 wt%), drying temperature and time(160${\circ}C$, 10 min), heat treatment temperature and time(500${\circ}C$, 20 min), respectively. ANOVA analysis suggested that the influence of the factors within ${\alpha}$=0.1 was significant with a 90% confidence level.

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.10a
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• pp.136-136
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• 1997

• Bulletin of the Korean Chemical Society
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• v.6 no.6
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• pp.344-347
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• 1985

Perovskite type oxides of $SrTiO_3,SrZrO_3,and\;SrTi_{1-x}Zr_xO_3$ have been systematically synthesized at $1250^{\circ}C$and $1550^{\circ}C$ with specimens containing additions of up to x=0.9 of zirconium by solid state reactions and characterized by X-ray diffraction. X-ray diffraction studies showed that the compound $SrTi_{1-x}Zr_xO_3$ has cubic structure. The lattice paramters of $SrTi_{1-x}Zr_xO_3$ solid solutions obey the Vegard's law and fairly large increase in volume can acompany the formation of this solution with increasing Zr content(X). Assuming the lattice constants of perovskite type compounds $A(B_{1-x}B'_x)O_3$where $B_{1-x}B'_x$ is $Ti_{1-x}Zr_x$, to be a linear function of the ionic radii of B and B' ions, the disordered ion pair of $Ti^{4+}$and $Zr^{4+}$ was verified from the lattice constants of a series compounds varying x=0,0.05, 0.25, 0.5, 0.75, 0.9, and 1.0 with known isovalent pairs.

• Journal of the Korean Ceramic Society
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• v.35 no.8
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• pp.791-794
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• 1998

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.533-540
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• 1997

The microwave dielectric properties of ((P $b_{1-x}$ C $a_{x}$)Zr $O_3$ and (P $b_{0.63}$,C $a_{0.37-x}$ $M_{x}$)Zr $O_3$(M=Mg,Sr) ceramics were investigated. In (P $b_{1-x}$ C $a_{x}$)Zr $O_3$ (X=0.33~0.40) ceramics, high quality factor and small temperature coefficient of resonant frequency were obtain in (P $b_{0.63}$C $a_{0.37}$)Zr $O_3$with perovskite structure. In the case of (P $b_{0.63}$C $a_{0.37-x}$M $g_{x}$)Zr $O_3$ dielectric constant temperature coefficient of resonant frequency increased and quality factor decreased due to increase of polarization of A-O bonding. When replacing Ca ion with Sr ion with large ion radius, polarization decreased with increased of bonding length and thus dielectric constant and temperature coefficient of resonant frequency decreased.decreased.creased.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.302-302
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• 2007

The $SrRuO_3$/Si thin film electrodes are grown with (00l) preferred orientations on SrO buffered-Si (001) substrates by pulsed laser deposition. The optimum conditions of SrO buffer layers for $SrRuO_3$ preferred orientations are the deposition temperature of $700^{\circ}C$, deposition pressure of $1\;{\times}\;10^{-6}\;Torr$, and the thickness of 6 nm. The 100nm thick-$SrRuO_3$ bottom electrodes deposited above $650^{\circ}C$ on SrO buffered-Si (001) substrates have a rms roughness of approximately $5.0\;{\AA}$ and a resistivity of 1700 -cm, exhibiting a (00l) relationship. The 100nm thick-$Pb(Zr_{0.2}Ti_{0.8})O_3$ thin films deposited at $575^{\circ}C$ have a (00l) preferred orientation and exhibit $2P_r$ of $40\;C/cm^2$, $E_c$ of 100 kV/cm, and leakage current of about $1\;{\times}\;10^{-7}\;A/cm^2$ at 1V.

• Korean Journal of Materials Research
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• v.10 no.9
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• pp.607-611
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• 2000

Zr modified $(Ba_{1-x},Sr_x)TiO_3$ thin films as capacitor for high density DRAM were deposited by r.f. magnetron sputtering. The films deposited at various chamber pressure exhibited a polycrystalline structure. The Zr/Ti ratio of the films increased significantly with decreasing the chamber pressure and this variation affected the microstructure and surface roughness of films When chamber pressure increased dielectric constant of the films effected due to decrease of Zr. The thin films prepared in this study show dielectric constant of 380 to 525 at 100KHz. The variation of capacitance and polarization measured as a function of bias voltage suggested that all films were paraelectric phases. Leakage current exhibited smaller value as chamber pressure decrease and the leakage current density of the films deposited above 10mTorr was $10^{-7}~10^{-8}A/cm^2$ order at 200kV/cm. $(Ba_{1-x},Sr_x)(Ti_{1-y},Zr_y)O_3$ thin films in this study appeared to be potential thin film capacitor for high density DRAM.

• Proceedings of the Korean Ceranic Society Conference
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• 2004.10a
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• pp.79.2-79.2
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• 2004