• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.503-507
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• 1998

Sintering behavior and dielectric peroperties of $xCaTiO_3-La(Zn_{1/2}Ti_{1/2})O_3$ system were investigated for better understanding of the microwave dielectric materials. In $xCaTiO_3-(1-x)La(Zn_{1/2}Ti_{1/2})O_3$ systems, solid solution type was focused as a function of composition(x=0.4-0.6) and sintered density. With increasing the sintered density, the relative dielectric constant was decreased and Q value was increased and then saturated. In solid solution type, dielectric constant was increased with increasing $CaTiO_3$ content. In $0.5\;CaTiO_3-0.5\; La(Zn_{1/2}Ti_{1/2})O_3$ case, dielectric constant(=48) and temperature coefficient of resonace frequency$(=-1 ppm/^{\circ}C$) were obtained.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.1-6
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• 2000

In this paper, organic dispersion type back light EL(Electroluminescent) devices were manufactured using Ethyl hydroxy ethyl cellulose as organic binder, ZnS:Cu as phosphor powder and $BaTiO_3$ as dielectrics by screen printing method, which are focused on as a new light source. The properties of the fabricated organic dispersion type back light EL devices were showed $1.98[mA/\m^2]$ of current density, 0.075[W] of power consumption, 7.1[nF] of capacitance at $25[^{\circ}C]$, 100[V], 400[Hz], respectively. Also brightness of the fabricated device was revealed $20~110[cd/\m^2]$ at 50~150[V] and the change of color was shoed bluish green of x=0.1711, y=0.3676 which are color coordinate by CIE.

• Journal of the Korean Ceramic Society
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• v.34 no.3
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• pp.281-288
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• 1997

The effects of 0 to 6 mol% excess 91PbO-9WO3 addition on the microstructure and the dielectric pro-perties in 40Pb(Mg1/3Nb2/3)O3-30PbTiO3-30Pb(Mg1/2W1/2)O3 ternary system were investigated. Excess 91PbO-9WO3 addition enhanced densification at relatively lower temperature due to the formation of liquid phase. The dielectric constant of the specimen with standard composition was 16,400 and that of specimen with 1 mol% excess additive was the maximum of 18,500. And more than 2 mol% excess addition decreased dielec-tric constant. Specimens with 2~4 mol% 91PbO-9WO3 addition showed dual peak maxima in the tem-perature dependence of dielectric constant. In the specimens which have more than 5 mol% excess addition a new phase with W-rich composition was formed at grain boundary.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.7
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• pp.58-64
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• 2006

Recently deep interests have been paid on the effective generation of ozone, which has been widely used for water treatment, deodorization, color removal, and chemical processing of exhausted smoke. The silent discharge reaction has been proposed as the most effective one in the many ozone generation methods, because the silent discharge can be generated under the conditions of lower applied voltage and power consumption, compared other ones. In this paper, in order to improve the ozone generation and ozone generation efficiency, the conventional silent discharge chamber with $Al_2O_3$ dielectric layer and tubular ferroelectric bed discharge reactor packed with $Al_2O_3$ pellets were made, and the silent discharge of the reactors were studied experimentally. The ozone generation characteristics are also discussed based on the discharge characteristics, especially on the wall charge accumulation properties and power consumption. The results show that the electric charges of discharge tube with bead are around 2.5 times as large as those without bead. In the discharge chamber packed with dielectric beads, the ozone concentration and the energy yield characteristics were also improved, compared with those in the conventional silent discharge reactor.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.7
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• pp.1491-1496
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• 2005

We fabricated the $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of $100\%$ perovskite phase by drying at $350^{\circ}C$ after each coating and final annealing at $650^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the $Pt/Ti/SiO_2/Si$ substrate and its dielectric constant and leakage current density were measured as 936 and $1.1{\mu}A/cm^2$, respectively.

• Transactions on Electrical and Electronic Materials
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• v.4 no.3
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• pp.34-37
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• 2003

[ $HfO_2$ ] and $HfO_xN_y$ films were deposited by plasma-enhanced chemical vapor deposition using $Hf[OC(CH_3)_3]_4$ as the precursor in the absence of $O_2$. The crystallization temperature of the $HfO_xN_y$ films is higher than that of the $HfO_2$ film. Nitrogen incorporation in $HfO_xN_y$ was confirmed by auger electron spectroscopy analysis. After post deposition annealing (PDA) at 800$\Box$, the EOT increased from 1.34 to 1.6 nm in the $HfO_2$ thin films, whereas the increase of EOT was suppressed to less than 0.02 nm in the $HfO_xN_y$. The leakage current density decreased from 0.18 to 0.012 $A/cm^2$ with increasing PDA temperature in the $HfO_2$ films. But the leakage current density of $HfO_xN_y$ does not vary with increasing PDA temperature because an amorphous $HfO_xN_y$ films suppresses the diffusion of oxygen through the gate dielectric.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.371-374
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• 2004

저온동시 소성용(low temperature co-fired ceramics, LTCC) 마이크로파 유전체을 만들기 위해 $Ca(Li_{1/4}Nb_{3/4})O_3$ 마이크로파 유전체 세라믹스에 zinc-borosililcate glass를 첨가하여 소결 특성과 마이크로파 유전 특성을 조사하였다. $Ca(Li_{1/4}Nb_{3/4})O_3$과 $0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$에 zinc-borosilicate를 $5{\sim}30wt%$ 첨가하여 소결한 결과 $875{\sim}925^{\circ}C$에서 동시 소성이 가능한 것으로 확인되었으며 zinc-borosilicate glass의 함량이 증가할수록 저온에서 소성이 가능하였지만 과량의 액상과 2차상이 형성되면서 유전율과 품질계수가 저하되는 경향을 나타내었다. $Ca(Li_{1/4}Nb_{3/4})O_3$에 5wt%의 zinc-borosilicate를 첨가하여 $900^{\circ}C$에서 소성한 결과 가장 우수한 유전 특성$(\epsilon_r=17.45,\;Q{\times}f_0=5487)$을 나타내었고, 유전율을 높이기 위해 $CaTiO_3$를 0.3mol% 첨가한 $0.7Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$에 10wt%의 zinc-borosilicate를 첨가하여 $925^{\circ}C$에서 소성한 결과 가장 우수한 유전특성$(\epsilon_r=44.92,\;Q{\times}f_0=5567)$을 나타내었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.05a
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• pp.39-43
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• 1993

Electricial characteristics of gate dielectrics prepared by reoxidation of thermal $SiO_2$ in nitrous oxide gas have been investigated. 10 and 19nm-thick oxides were reoxidized at temperatures of $900-1000^{\circ}C$ for 10-60 min in $N_2O$ ambient. As reoxidation proceeds, it is shown that nitrogen concentration at $Si/SiO_2$ interface increases gradually through the AES analysis. Nitrogen pile-up at $Si/SiO_2$ interface acts as a oxidant diffusion barrier that reduces the oxidation rate significantly. And it not only strengthen oxynitride structure at the interface but improve the gate dielectric qualities. Reliabilities of oxynitride films are conformed by the breakdown distributions and constant current stress technique. Therefore, the oxynitride films made by this process show a good promise for future ULSI applications.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.273-279
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• 2014

Hexagonal Ba-ferrites are widely suggested as materials for small antennas. In this paper, the sintering behavior and magneto-electric properties of $Ba_3Co_{2-2x}Mn_{2x}Fe_{24}O_{41}$ ($0.1{\leq}x{\leq}0.5$) ceramics were investigated for small antenna application. All samples of $Ba_3Co_{2-2x}Mn_{2x}Fe_{24}O_{41}$ ceramics were prepared by the solid-state reaction method and sintered at $1250^{\circ}C$. From the XRD patterns of the sintered $Ba_3Co_{2-2x}Mn_{2x}Fe_{24}O_{41}$ceramics, the Z-type phases were found to be the main phases. The real part of permittivity and permeability of the $Ba_3Co_{2-2x}Mn_{2x}Fe_{24}O_{41}$ceramics decreased with frequency. On the other hand, loss tangents of permittivity and permeability tended to behave opposite to real part of permittivity and permeability. The real part of permeability was affected by Mn additions. The real part of permittivity, the loss tangent of permittivity and the real part of permeability, the loss tangent of permeability of $Ba_3Co_{0.2}Mn_{0.8}Fe_{24}O_{41}$ ceramics were 19.774, 0.176 and 15.183, 0.073, respectively, at 510 MHz. In order to investigate the effect of magneto-dielectric ceramics on antenna, PIFA (Planar Inverted F Antenna) was simulated with CST (Computer Simulation Technology). The operating frequency of antenna was decreased without considerable change of bandwidth by using the $Ba_3Co_{0.2}Mn_{0.8}Fe_{24}O_{41}$ ceramics as the carrier.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.17-20
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• 2001

Nonvolatile semiconductor memory devices with reoxidized nitrided oxide(RONO) gate dielectrics were fabricated, and nitrogen distribution and bonding species which contribute to memory characteristics were analyzed. Also, memory characteristics of devices depending on the anneal temperatures were investigated. The devices were fabricated by retrograde twin well CMOS processes with $0.35{\mu}m$ Nonvolatile semiconductor memory devices with reoxidized nitrided oxide(RONO) gate dielectric were fabricated, and nitrogen distribution and bonding species which contributing memory characteristics were analyzed. Also, memory characteristics of devices according to anneal temperatures were investigated. The devices were fabricated by $0.35{\mu}m$ retrograde twin well CMOS processes. The processes could be simple by in-situ process of nitridation anneal and reoxidation. The nitrogen distribution and bonding state of gate dielectric were investigated by Dynamic Secondary Ion Mass Spectrometry(D-SIMS), Time-of-Flight Secondary Ion Mass Spectrometry(ToF-SIMS), and X-ray Photoelectron Spectroscopy(XPS). Nitrogen concentrations are proportional to nitridation anneal temperatures and the more time was required to form the same reoxidized layer thickness. ToF-SIMS results show that SiON species are detected at the initial oxide interface and $Si_{2}NO$ species near the new $Si-SiO_{2}$ interface that formed after reoxidation. As the anneal temperatures increased, the device showed worse retention and degradation properties. These could be said that nitrogen concentration near initial interface is limited to a certain quantity, so excess nitrogen are redistributed near the $Si-SiO_{2}$ interface and contributed to electron trap generation.