• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2002.11a
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• pp.69-71
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• 2002

$(Bi, La)Ti_{3}O_{12}(BLT)$ ferroelectric thin films were prepared on $Al_{2}O_{3}/Si$ substrates by the sol-gel method. The as-coated films were post-annealed at the temperature of $650^{\circ}C$ and $700^{\circ}C$ for 30 min. The crystallinty, surface morphologies and electrical properties were affected by the annealing temperatures. The BLT films annealed at above $650^{\circ}C$ exhibited typical bismuth layered perovskite structures with (00$\ell$) preferred orientation. The granular shaped grains with a size of approximately 90nm was formed in the film sample annealed at $700^{\circ}C$. The memory window volatge of the BLT film was 2.5V. The leakage current of BLT films annealed at $650^{\circ}C$ was about $1\times10^{-7}A/\textrm{cm}^2$ at 3V.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1199-1203
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• 2012

Catalytic filters consisting of Ni nanoparticle and carbon fiber with different oxidation states of Ni (either metallic or oxidic) were prepared using a chemical vapor deposition process and various post-annealing steps. CO oxidation reactivity of each sample was evaluated using a batch type quartz reactor with a gas mixture of CO (500 mtorr) and $O_2$ (3 torr) at $300^{\circ}C$. Metallic and oxidic Ni showed almost the same CO oxidation reactivity. Moreover, the CO oxidation reactivity of metallic sample remained unchanged in the subsequently performed second reaction experiment. We suggested that metallic Ni transformed into oxidic state at the initial stage of the exposure to the reactant gas mixture, and Ni-oxide was catalytically active species. In addition, we found that CO oxidation reactivity of Ni-oxide surface was enhanced by increase in the $H_2O$ impurity in the reactor.

• Journal of Magnetics
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• v.14 no.1
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• pp.18-22
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• 2009

The shape anisotropy effect of a giant magnetoresistance-spin valves (GMR-SV) device with a glass/NiO/NiFe/CoFe/Cu/CoFe/NiFe layered structure for use in the detection of magnetic property of molecules within a cell was investigated. The patterned device was given uniaxial anisotropy during the sputtering deposition and vacuum post-annealing, which was performed at $200^{\circ}C$ under a 300 Oe magnetic field. The pattern size of the device, which was prepared through the photolithography process, was $2{\times}15\;{\mu}m^2$. The experimental results confirmed that the best design for a GMR-SV device to be used as a biosensor is to have both the axis sensing current and the easy axis of the pinned NiO/NiFe/CoFe triple layer oriented in the direction of the device's width, while the easy axis of the free CoFe/NiFe bilayer should be pointed along the long axis of the device.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.47-50
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• 2000

This paper investigated structural and electrical properties of $Y_2$ $O_3$ as a buffer layer of single transistor FRAM (ferroelectric RAM). $Y_2$ $O_3$ buffer layers were deposited at a low substrate temperature below 40$0^{\circ}C$ and then RTA (rapid thermal anneal) treated. Investigated parameters are substrate temperature, $O_2$ partial pressure, post-annealing temperature, and suppression of interfacial $SiO_2$ layer generation. For a well-fabricated sample, we achieved that leakage current density ( $J_{leak}$) in the order of 10$^{-7}$ A/$\textrm{cm}^2$, breakdown electric field ( $E_{br}$ ) about 2 MV/cm for $Y_2$ $O_3$ film. Capacitance versus voltage analysis illustrated dielectric constants of 7.47. We successfully achieved an interface state density of $Y_2$ $O_3$/Si as low as 8.72x1010 c $m^{-2}$ e $V^{-1}$ . The low interface states were obtained from very low lattice mismatch less than 1.75%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.558-561
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• 2001

Vanadium oxide ($VO_{x}$) thin films are very good candidate material for uncooked infrared (IR) detectors due to their high temperature coefficient of resistance (TCR) at room temperature. But, the deposition of $VO_{x}$ thin films showing good electrical properties is very difficult in micro bolometer fabrication process using sacrificial layer removal because of its low process temperature and thickness of thin films less than 1000${\AA}$. This paper presents a new fabrication process of $VO_{x}$ thin films having high TCR and low resistance. Through sandwich structure of $VO_{x}$(100${\AA}$)/V(80${\AA}$)/$VO_{x}$(500${\AA}$) by sputter method and post-annealing at oxygen ambient, we have achieved high TCR more than -2%/$^{\circ}C$ and low resistance less than $10K\Omega$ at room temperature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.6
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• pp.487-490
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• 2007

In this paper, the formation and thermal stability characteristics of Ni silicide using Ni-V alloy on Boron cluster ($B_{18}H_{22}$) implanted bulk and SOI substrate were examined in comparison with pure Ni for nano-scale CMOSFET. The Ni silicide using Ni-V alloy on $B_{18}H_{22}$ implanted SOI substrate after high temperature post-silicidation annealing showed the lower sheet resistance, no agglomeration interface image and lower surface roughness than that using pure Ni. The thermal stability of Ni silicide was improved by using Ni-V alloy on $B_{18}H_{22}$ implanted SOI substrate.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.5
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• pp.458-462
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• 2008

In this paper, we investigated the (002) preferred orientation and morphology characteristics of AlN thin film by using reactive rf sputtering. Additionally, AlN thin films grown in the range from 150 to 300 W were studied under room temperature without substrate heating and post annealing. Sputtered AlN thin films were well grown on Si substrates and the (002) main peak in XRD patterns showed the highest intensity at 300 W with $0.25^{\circ}$ degree of full width at half-maximum (FWHM). As increased RF power, the surface roughness was increased from 1.0 to 3.4 nm. In Fourier transformation infrared spectroscopy (FTIR), $A_1$ (TO) and $E_1$ (TO) mode closed to AlN thin film confirmed the changes with increasing the intensity rate. From these results, we could confirm a chance of the growth of AlN thin film by only low temperature.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1156-1158
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• 1993

Undoped ZnO films were prepared on Soda lime glass using pyrosol deposition method starting from the solutions composed of $ZnO(CH_3COO){_2}\;2H_2O-H_2O-CH_3OH$. Surface morphology revealed ZnO films were polycrystalline above $400^{\circ}C$ substrate temperature in $H_2O$ only solvent $H_2O-CH_3OH$ solvent revealed more good result than $H_2O$ only solvent. the lowest resistivity of as-deposit ZnO films was 4 ${\Omega}$-Cm and transmittance at 550nm was 85%. post-annealing of as-deposited films in a vacuum leads to s reduction in resistivity without affecting the optical transmittance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.33-36
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• 1999

In this paper, $Ba_{0.5}$Sr$_{0.5}$TiO$_3$ thin-films were prepared on Pt/Ti/Si0$_2$/Si substrates by RF magnetron sp-uttering method. We investigated electric and dielectric properties of BST thin-films with various ann-ealing temperature using in-sute RTA. Deposition conditions of BST films were set substrate temperat-ure, 30$0^{\circ}C$ and working gas ratio, Ar:O$_2$=90:10. After BST films deposited, we fabricated a capacitor of MIM structure with Al top electrode for measurement. Post-annealing using RTA performed at 40$0^{\circ}C$, $600^{\circ}C$, 80$0^{\circ}C$ for 60 sec, respectively. Also we exacted crystallization and composition of BST thin-films by XRD analysis. In measurement result, this capacitors showed a dielectric constant of about 200 at 1MHz and leakage current density of 5$\times$10$^{-8}$ A/$\textrm{cm}^2$ at 1.5V Microstructure of BST thin-films exhibited effective quality in low-temperature annealed 71ms than high-temperature annealed 71ms.s.s.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.128-131
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• 2009

Silicon carbide (SiC) has attracted significant attention for high frequency, high temperature and high power devices due to its superior properties such as the large band gap, high breakdown electric field, high saturation velocity and high thermal conductivity. We performed Al ion implantation processes on n-type 4H-SiC substrate using a SILVACO ATHENA numerical simulator. The ion implantation model used Monte-Carlo method. We simulated the effect of channeling by Al implantation in both 0 off-axis and 8 off-axis n-type 4H-SiC substrate. We have investigated the effect of varying the implantation energies and the corresponding doses on the distribution of Al in 4H-SiC. The controlled implantation energies were 40, 60, 80, 100 and 120 keV and the implantation doses varied from $2{\times}10^{14}$ to $1{\times}10^{15}\;cm^{-2}$. The Al ion distribution was deeper with increasing implantation energy, whereas the doping level increased with increasing dose. The effect of post-implantation annealing on the electrical properties of Al-implanted p-n junction diode were also investigated.