• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 C
• /
• pp.1488-1490
• /
• 1997

$(Pb_{1-x}La_x)Ti_{1-x/4}O_3$ (x=0, 0.02, 0.04, 0.06, 0.08) ceramic thin films were fabricated by Sol-Gel method. A stock solution of (Pb,La)$TiO_3$ with excess Pb 10mol% was made and spin-coated on the Pt/Ti/$SiO_2$/Si substrate at 4000rpm for 30 seconds. Coated specimens were dried on the hot-plate at $350^{\circ}C$ for 10 min and sintered at $500{\sim}750^{\circ}C$ for 1 hour. The dielectric constant, remanent polarization and coercive field of the PLT(6 at.%) thin films sintered at $650^{\circ}C$ were 884, $13.95{\mu}C/cm^2$ and 8.7kV/cm, respectively. Pyroelectric coefficient, figure of merit of pyroelectric current, voltage responsivity and detectivity of PLT(6at.%) thin films were $3.2{\times}10^{-8}\;C/cm^2K$, $1.02{\times}10^{-8}\;C{\cdot}cm/J$, $2.9{\times}10^{-11}\;C{\cdot}cm/J$, $0.29{\times}10^{-8}\;C{\cdot}cm/J$, respectively.

• 마이크로전자및패키징학회지
• /
• 제3권2호
• /
• pp.27-38
• /
• 1996

Lithium fluorhectorite 결정상을 함유한 glass ceramics 분말의 형성과 제조된 glass ceramics 분말을 이용한 저온 소결기판의 특성평가를 하였다. Li2O-MgO-MgF2-SiO2 계 유 리로 핵형성 및 결정 성장을 실시하여 lithium fluorhectorite 결정상을 지닌 glass ceramics 를 제조하였다. 유리시편의 핵형성 온도는 46$0^{\circ}C$였고 결정성장온도는 600, 640, 110$0^{\circ}C$에서 나타났다. $600^{\circ}C$에서의 결정상으 Li2.4LiSi4O10F2가 나타났다. Li2.4Mg8LiSi4와 Li2.8Mg0.6SiO4은 lithium fluorhectorite 결정상으로 되기 위한 중간상임을 확인할수 있었다. 64$0^{\circ}C$에서 열처리 후 110$0^{\circ}C$에서 재열처리하여 형성된 결정은 lithium fluorhectorite 와 tridymite가 최종 결정 상으로 나타났다. 이것은 수중에서 water swelling 현상에 의하여 분말화할 수 있었다, 기판 제조용 slurry를 제조하기 위해 glass ceramics 분말에 Al2O3분말을 0,25,50wt%로 혼합한것 과 glass ceramics 분말에 potashborosilica-te glass 분말을 15, 30, 45, 60 wt% 로 배합하 여 doctor blade 법으로 green sheet를 제조하였다. green sheet 는 950~150$0^{\circ}C$로소성하여 기판의 특성을 평가하였다. 겉보기 기공율은 3.06~19,14%이었고, 전기적 특성으로 유전상수 는 3~5(100KHz)를 나타내었다.

• 한국전기전자재료학회논문지
• /
• 제27권2호
• /
• pp.132-135
• /
• 2014

The Sr based ceramic thin films were deposited on Si substrate by RF magnetron sputtering method. And Sr based thin films were annealed at $500{\sim}700^{\circ}C$ using RTA. The surface roughness showed about 2.4 nm in annealed thin film at $600^{\circ}C$. The capacitance density of Sr based thin films were increased with the increase of annealing temperature. The maximum capacitance density of $0.6{\mu}F/cm^2$ was obtained by annealing temperature at $700^{\circ}C$. The voltage dependence of dielectric loss showed about 0.02 in voltage ranges of -10~+10 V. The leakage current density of annealing temperature of $600^{\circ}C$ was the $4.0{\times}10^{-6}\;A/cm^2$ at applied voltage of -5~+5 V.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
• /
• pp.314-314
• /
• 2008

The low temperature sintering and the dielectric properties of $Al_2O_3/SiO_2$-zinc borosilicate glass composites were investigated in the view of the application for LTCC. When the sintering was conducted at $900^{\circ}C$ $ZnAl_2O_4$ and $ZnB_2O_4$ compounds formed at the $Al_2O_3$-rich and the $SiO_2$-rich compositions, respectively. The reaction between ZBS glass and $Al_2O_3/SiO_2$ caused the formation of these compounds. The $Al_2O_3/SiO_2$ ratio affected the dielectric properties. The excellent dielectric properties, i.e., Q$\times$f value= 40,000 GHz and ${\varepsilon}_r$=4.5, were obtained in the $Al_2O_3/SiO_2$-ZBS glass system and fabricated the LTCC substrate materials.

• Bulletin of the Korean Chemical Society
• /
• 제30권1호
• /
• pp.92-96
• /
• 2009

A new precursor [$Zr(acac)_{3}(H_{2}O)_{2}$] was synthesized by Sonochemical technique and used to deposit thin $ZrO_{2}$ film on quartz and ceramic substrate via ultrasonic aerosol assisted chemical vapour deposition (UAACVD) at 300 ${^{\circ}C}$ in oxygen environment followed by annealing of the sample for 2-3 minutes at 500 ${^{\circ}C}$ in nitrogen ambient. The molecular structure of the precursor determined by single crystal X-ray analysis revealed that the molecules are linked through intermolecular hydrogen bonds forming pseudo six and eight membered rings. DSC and TGA/FTIR techniques were used to determine thermal behavior and decomposition temperature of the precursor and nature of evolved gas products. The optical measurement of annealed $ZrO_{2}$ film with tetragonal phase shows optical energy band gap of 5.01 eV. The particle size, morphology, surface structure and composition of deposited films were investigated by XRD, SEM and EDX.

• Journal of the Optical Society of Korea
• /
• 제8권1호
• /
• pp.6-12
• /
• 2004

Diffraction Bragg gratings consisting of metal (silver) nanoparticles are generated inside a soda-lime glass substrate. After ion-exchanging and annealing processes in the glass, the silver nanoparticles are first formed with the particle diameters of 10 nm ∼ 30 nm. By interfering two CW laser beams at ∼ 60 ${\mu}{\textrm}{m}$ deep under the surface of the nanoparticles-dispersed glass, Bragg gratings with thickness of 15 ${\mu}{\textrm}{m}$ and period of 3.5 ${\mu}{\textrm}{m}$ are generated. Diffraction efficiency of the gratings formed by two TE-polarized beams is three times higher than that by two TM-polarized beams. From this polarization dependence, we have found that strong coupling of the surface plasmons induced on the metal particles may contribute dominantly to generate the diffraction grating.

• 한국통신학회논문지
• /
• 제28권8A호
• /
• pp.607-612
• /
• 2003

본 논문에서는 무선 통신 시스템의 SOP(System-On-Package)를 위하여 LTCC(Low Temperature Co-fired Ceramic)를 이용하여 다층구조의 초소형 병렬결합 대역통과 여파기를 제안하였다. 제작된 대역통과 여파기는 106$\mu\textrm{m}$의 두께인 LTCC sheet가 5층으로 구성되었고 크기는 5.24mm $\times$ 4.3mm$\times$ 0.53mm이다. 측정된 대역통과 여파기는 중심주파수 5.8GHz에서 200MHz의 대역폭을 가지며, 통과대역에서 13.679㏈의 반사손실과 2.326㏈의 삽입손실, 그리고 4.7GHz에서 28.052㏈의 감쇄특성을 갖는다.

• E2M - 전기 전자와 첨단 소재
• /
• 제10권6호
• /
• pp.541-547
• /
• 1997

(Pb$_{1-x}$ La$_{x}$)Ti$_{1-x}$ $_4$O$_3$(x=0, 0.02, 0.04, 0.08) ceramic thin films were fabricated by Sol-Gel method. A stock solution of (Pb, La)TiO$_3$ with excess Pb 10 mol% was made and spin-coated on the Pt/Ti/SiO$_2$/Si substrate at 400rpm for 30 seconds. Coated specimens were dried on the hot-plate at 35$0^{\circ}C$ for 10 min and sintered at 500~75$0^{\circ}C$ for 1 hour. The dielectric constant, remanent polarization and coercive field of the PLT(6at.%) thin films sintered at $650^{\circ}C$ were 884, 13.95$\mu$C/$\textrm{cm}^2$ and 8.7kV/cm, respectively. Pyroelectric coefficient, figure of merit of pyroelectric current, voltage responsivity and detectivity of PLT(6at.%) thin films were 3.2$\times$10$^{-8}$ C/$\textrm{cm}^2$K, 1.02$\times$10$^{-8}$ C.cm/J, 2.9 $\times$10$^{-11}$ C.cm/J, 0.29$\times$10$^{-8}$ C.cm/J, respectively.ely.

• 한국전자파학회논문지
• /
• 제20권3호
• /
• pp.215-221
• /
• 2009

본 논문에서는 차량 GPS 안테나로 사용할 수 있는 프랙털 구조의 사다리꼴 마이크로스트립 패치 안테나를 설계하고 이를 제작하였다. 기판 손실을 없애고 이득을 향상시키기 위하여 공기층을 갖는 패치 안테나로 설계하였다. 사다리꼴 패치에 프랙털 구조의 적용과 슬롯의 부설로 일반 삼각형 패치 안테나 면적 대비 42.5 %크기로 소형화시켰다. 제작 후 측정한 결과, VSWR 2:1 기준으로 GPS 대역을 포함한 200 MHz의 대역폭을 얻었다. 이득은 공진주파수에서 4.31 dBi로 일반 세라믹 패치 안테나의 이득보다 GPS 대역에서 2$\sim$5 dB 높은 이득을 얻었다.

• The Korean Journal of Ceramics
• /
• 제6권4호
• /
• pp.354-358
• /
• 2000

The SnO$_2$film was deposited on a corning glass 1737 substrate by plasma enhanced chemical vapor deposition using a gas mixture of SnCl$_4$, $O_2$, and Ar. The film thickness was measured using $\alpha$-step and was about 9400$\AA$. The conventional X-ray diffractometry and pole figure attachment were used to refine the crystal structure of SnO$_2$ thin film. Six pole figures, (200), (211), (310), (301), (321), and (411), were measured with CoK$_\alpha$ radiation in reflection geometry. The X-ray diffraction data were measured at room temperature using CuK$_\alpha$ radiation with graphite monochromator. The agreement between calculated and observed patterns for the normal direction of SnO$_2$ thin film was not satisfactory due to the severely preferred orientation effect. The Rietveld refinement of heavily textured SnO$_2$ thin film was successfully achieved by adopting the pole density distribution of each reflection obtained from the inverse pole figure as a correction factor for the preferred orientation effect. The R-weighted pattern, R$_wp$, was 15.30%.