• 전기학회논문지
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• 제56권1호
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• pp.128-131
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• 2007

YBaCuO superconducting ceramic thick films were fabricated by chemical process. YBaCuO films have been successfully grown on $SrTiO_3$ substrates without a template layer. The films show poor or non superconductivity although they have excellent crystalline properties. ion channeling measurement made it clear that the strain in the films due to strong chemical bonding between the substrate and epilayer remains, resulting in the poor superconductivity. The X ray diffraction pattern of the YBaCuO thick films contained 90K phase. The self template method have resolved this problem. We obtained high-Jc as-grown YBaCuO on $SrTiO_3$ (100).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.613-616
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• 2001

Bi$_2$Sr$_2$CuO$_{x}$ thin films have been fabricated by atomic layer-by-layer deposition using ion beam sputtering(IBS) method. During the deposition, 10 and 90 wt%-ozone/oxygen mixture gas of typical pressure of 1~9$\times$10$^{-5}$ Torr are supplied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then Bi-2201 oriented along the c-axis is grown.n.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.239-242
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• 1998

The (S $r_{0.85}$C $a_{0.15}$)Ti $O_3$ (SCT) thin films are deposited on Pt-coated electrode using RF magnetron sputtering method at various substrate temperature. Dielectric constant of SCT thin films is increased with increased as the deposition temperature and changes almost linearly in temperature ranges from -80 to +90[$^{\circ}C$]. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films is observed above 200[kHz]. V-I characteristics of SCT thin films show the increasing leakage current with the increases of deposition temperature.ure.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.866-869
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• 2001

In this study, (Ba,Sr)TiO$_3$(BST) thin films were etched with a magnetically enhanced inductively coupled plasma(MEICP). Etching characteristics of BST thin films including etch rate and selectivity were evaluated as a function of the etching parameters such as gas mixing ratio, rf power, dc bias voltage and chamber pressure. The maximum etch rate of the BST films was 1700 $\AA$/min at Ar(90)/CF$_4$(10), 600 W/350 V and 5 mTorr. The selectivity of BST to PR was 0.6, 0.7, respectively. To analyze the composition of surface residue remaining after the etching, samples etched with different CF$_4$/Ar gas mixing ratio were investigated with X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). From the results of XPS and SIMS, there are chemical reaction between Ba, Sr, Ti and C, F radicals during the etching and remained on the surface.

• 한국전기전자재료학회논문지
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• 제14권10호
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• pp.855-860
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• 2001

Bi$_2$Sr$_2$CuO$_{x}$(Bi-2201) thin film were fabricated by atomic layer-by -layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed oxygen were used with ultraviolet light irradiation to assist oxidation. XRD and RHEED investigations revealed that a buffer layer is formed at the early stage of deposition (less than 10 unit cell), and then c-axis oriented Bi-2201 grows on top of it.t.

• KSBB Journal
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• 제28권3호
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• pp.165-169
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• 2013

In this study, 52 ureolytic bacterial strains were newly isolated from various environments. From these, 2 strains (TB-15 and TB-22) were selected based on their high urease activity. XRD spectra clearly showed presence of various sequestration products such as calcite and strontianite in samples. TB-22 showed 20~30% higher survivability upon Sr concentration (20 mM) than Sporosarcina pasteurii KCTC 3558. TB-15 and TB-22 showed 80~90% higher survivability at pH 6 than S. pasteurii. The results demonstrated that the 2 isolates colud be good candidates for the bioremediation of Sr contaminated sites.

• Progress in Superconductivity
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• 제1권2호
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• pp.95-98
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• 2000

We have studied critical currents of $YBa_2Cu_3O_7$ step-edge junctions with different step orientations with respect to the major axes of $SrTiO_3$ (100) substrates. The junctions were prepared by pulsed laser deposition and argon ion milling with photoresist mask. We investigated current-voltage characteristics and critical current of the junctions as a function of the angle. The junction critical current showed an angle dependent modulation with maxima near 0 or 90 degree and minima near 45 and 135 degrees. The experimental results were analyzed based on the microstructure of the junction along the step and the d-wave symmetry of $YBa_2Cu_3O_7$ superconductor.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.244-247
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• 2002

NdBaCuO thin films were prepared on $SrTiO_{3}$ substrates by RF magnetron sputtering. These as-grown films were classified into 3type. The resistivity of the deposited films are usually lower than of the YBCO film. The Tc (onset) and Tc (R=0) in the optimized thin films are as high as 90 and 80K, respectively. These as-grown films are highly uniform and semi-trans parent and have a room temperature resistivity of $0.3m{\Omega}cm$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.529-530
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• 2006

$Bi_2Sr_2CuO_x$ thin films have been fabricated by atomic layer-by-layer deposition using the ion beam sputtering method. During the deposition, 10 and 90 wt%-ozone/oxygen mixture gas of typical pressure of $1{\sim}9{\times}10^{-5}\;Torr$ are supplied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then Bi-2201 oriented along the c-axis is grown.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3352-3358
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• 2021

Aiming at selective adsorption and separation of Y(III) from the Y(III)-Sr(II) group in acid solution, a silica-based TODGA impregnated adsorbent [(TODGA+1-dodecanol)/SiO₂-P-F600] has been prepared. Batch adsorption experiments were conducted under the effect of contact time, acid concentration, solution temperature, and adsorption capacity etc. Chromatography recovery of more than 90% Y(III) was successfully achieved under elution with 0.01 M DTPA solution in nitric acid adsorption system, and 0.1 M HCl solution in hydrochloride adsorption system, respectively.