• 한국표면공학회지
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• 제34권5호
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• pp.481-485
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• 2001

We investigated the structural and electrical properties of the Ba ($Zr_{x}$ $T_{il-x}$ )$O_3$ (BZT thin films with a mole fraction of x=0.2 and thickness 150 nm for the application in MLCC (Multilayer Ceramic Capacitor). BZT films were prepared on $Pt/SiO_2$/Si substrate at various substrate temperatures by the RF-magnetron sputtering system. When the substrate temperature was above $500^{\circ}C$, we could obtain multi-crystalline BZT films oriented at (110), (111), and (200) directions. The crystallization of the film and high dielectric constant were observed with the increase of substrate temperature. Capacitance of the film deposited at high temperature is more sensitive to the applied voltage than that of the film deposited at low temperature. This paper reports surface morphology, dielectric constant, dissipation factor, and C-V characteristics for BZT films deposited at three different temperatures. The BZT film deposited at 40$0^{\circ}C$ shows stable electrical properties but a little small dielectric constant for MLCC application.

• 자원리싸이클링
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• 제24권1호
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• pp.3-11
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• 2015

산 침출에 있어서 생성되는 가용성 실리카는 고액분리 시 여과를 어렵게 하고 목적금속의 순도를 저하시키는 등 습식제련공정에 있어서 큰 문제점으로 대두되고 있다. 따라서 본 고에서는 실리케이트 광물과 산과의 반응성, 가용성 실리카의 특성, 제거방법에 대하여 검토하였다. 가용성 실리카는 알카리 전처리에 의한 제거, 결정상태의 $SiO_2$로 변환, 응집 등의 방법을 통한 여과성 향상 등의 방법으로 처리할 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.291-293
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• 1997

In this study, Sol-Gel derived $(Ba_{0.7}Sr_{0.3})TiO_3$ thin films were fabricated and investigated. The stock solution was synthesized and spin-coated on Pt/Ti/$SiO_2$/Si substrate at 4000(rpm] and then, annealed at $650{\sim}750[^{\circ}C]$. Crystallization condition, microstructural properties and interfacial structure were observed by XRD, AFM, SEM and TEM. It was found that the BST thin films were completely crystallized at 750[$^{\circ}C$] and showed nano-sized grains. The dielectric constant and loss of the BST thin films were 220, 0.01 at 1[kHz] respectively. Increasing the temperature, the dielectric constant and loss characteristics were not varied widely. At the applied voltage of 1.5[V], the leakage current density was under the $10^{-9}[A/cm^2]$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.341-344
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• 1999

The effects of post annealing treatments of ferroelectrlclty in PZT(P $b_{1.05}$(Z $r_{0.52}$, $Ti_{0.48}$) $O_3$ thin film deposited on Pt/ $SiO_2$/Si substrate by RF-Magnetron sputtering methode was Investigated. Analyses by RTA(Rapid Thermal Annealing) treatments reveled that the crystallization process strongly depend on the healing temperature. The Perovskite structure with strong PZT (101) plan was obtained by RTA treatments at 75$0^{\circ}C$ With increasing RTA temperature of PZI thin films, the coercive field and remanent Polarization decreased, while saturation polarization( $P_{r}$) was decreased. P-E curves of Pt/PZT/Pt capacitor structures demonstrate typical hysteresiss loops. The measure values of $P_{r}$,. $E_{c}$ and dielectric constants by post annealed at 75$0^{\circ}C$ were 38 $\mu$C/$\textrm{cm}^2$ 35KV/cm and 974, respectively. Switching polarization versus fatigue characteristic showed 12% degradation up to 10$^{7}$ cycles.s.s.s.s.s.s.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.309-309
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• 2007

The LTCCs (low-temperature co-fired ceramics) are very important for electronic industry to build smaller RF modules and to fulfill the necessity for miniaturization of devices in wireless communication industry. The dielectric materials with sintering temperature $T_{sint}$<$900^{\circ}C$ are required. In this study, we investigated with glass-ceramic composition, which was crystallized with two crystals. The microstructure, crystal phases, thermal and mechanical properties, and dielectric properties of the composites were investigated using FE-SEM, XRD, TG-DTA, 4-point bending strength test and LCR measurement. The starting temperature for densification of a sintered body was at $779{\sim}844^{\circ}C$ and the glass frits were formatted to the crystal phases, $CaAl_2Si_2O_8$(anorthite) and $CaMgSi_O_6$(diopside), at sintering temperature. The sintered bodies exhibited applicable dielectric properties, namely 6-9 for ${\varepsilon}_r$. The results suggest that the glass-ceramic composite would be potentially possible to application of low dielectric L TCC materials.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.136-139
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• 1999

The post-annealing treatments on RF (Radio Frequency) magnetron sputtered PZI(Pb$\_$1.05/(Zr$\_$0.52/, Ti$\_$0.48/)O$_3$thin films(4000${\AA}$) have been investigated. for a structure of PZT/Pt/Ti/SiO$_2$/Si Crystallization pproperties of PZT films were strongly dependent on RTA(Rapid Thermal Annealing) annealing temperature. We were able to obtain a perovskite structure of PZT at a low temperature of 600$^{\circ}C$. P-E curves of Pd/PZT/Pt capacitor annealed at 700$^{\circ}C$ demonstrate typical hysteresis loops. The measured values of P$\_$r/, E$\_$c/, by post annealed at 700$^{\circ}C$ were 12.1 ${\mu}$C/$\textrm{cm}^2$, 120KV/cm respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.170-173
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• 2001

Thin films of phase-pure perovskite (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) were deposited in-situ onto Pt/Ti/ $SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. Two-step process to grow (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Electrical properties including dielectric constant, ferroelectric characteristics, crystallization and leakage current of PLT thin films were shown to be strongly inf1uenced by grain size. Also PLT thin films on p-type(100) Si substrate will be fabricated by pulsed laser deposition technique using a Nd:YAG laser with different wavelengths of 355, 532 and 1064 nm. Effect of the variation of laser wavelength on dielectric properties will be discussed. Microstructural and electrical properties of the film were investigated by C-V measurement leakage current measurement and SEM.ent and SEM.

• 공업화학
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• 제16권6호
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• pp.768-771
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• 2005

Silicon nitride ($SiN_x$) 박막이 상온에서 $SiO_2/Si$ 기판 위에 반응성 직류 마그네트론 스퍼터링 방법에 의하여 증착되었다. 증착된 $SiN_x$ 박막의 조성은 x-ray photoelectron spectroscopy를 이용하여 분석되었으며 Si가 풍부한 $SiN_x$ 박막이 증착되었음을 확인할 수 있었다. 증착된 $SiN_x$ 박막은 annealing 온도와 시간을 변화하여 annealing 되었다. X-ray diffraction (XRD) 분석이 $SiN_x$ 박막 내에 Si의 결정화를 조사하기 위해서 수행되었고, 박막의 광학적 특성과 전기적 특성들이 Si nanodot의 형성을 확인하기 위하여 측정되었다. 그 결과로써, XRD 분석에서 Si으로 예상되어지는 peak을 관찰할 수 있었으며 annealing 시간과 온도가 증가함에 따라서 $SiN_x$ 박막의 photoluminescence intensity는 점진적으로 증가하는 것이 관찰되었다. Annealing 전과 후에 측정된 $SiN_x$ 박막의 capacitance-voltage 특성으로부터 $SiN_x$ 박막 내에 존재하는 Si nanodot에 의하여 electron이나 hole의 trap 효과가 나타남을 예상할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.328-328
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• 2008

As a low K material for high frequency high integration modules, glass/ceramic composites were investigated. Glass composition were selected from $SiO_2-B_2O_3-Al_2O_3-R_2O$-RO system which having very low dielectric constant and cordierite was used as a ceramic filler. These composites were sintered at temperature range from $850^{\circ}$ to $950^{\circ}$ and XRD, SEM microstructure analysis of sintered bodies were performed for understanding sintering behavior. Any crystallization was not occurred and dense sintered bodies were attained. Dielectric and mechanical properties of these sintered glass/cordierite composites were analysed by network analyzer and UTM. Glass/ceramic composite with 50 wt% cordierite showing a dielectric constant (${\varepsilon}_r$) of 5.4, Q${\times}f_0$ (Q) of 1600 at 1 GHz and maximum bending strength of 163 MPa was attained.

• 대한금속재료학회지
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• 제48권2호
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• pp.133-140
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• 2010

10 nm thick Ni layers were deposited on 200 nm $SiO_2/Si$ substrates using an e-beam evaporator. Then, 60 nm or 20 nm thick ${\alpha}$-Si:H layers were grown at low temperature (<$200^{\circ}C$) by a Catalytic-CVD. NiSi layers were already formed instantaneously during Cat-CVD process regardless of the thickness of the $\alpha$-Si. The resulting changes in sheet resistance, microstructure, phase, chemical composition, and surface roughness with the additional rapid thermal annealing up to $500^{\circ}C$ were examined using a four point probe, HRXRD, FE-SEM, TEM, AES, and SPM, respectively. The sheet resistance of the NiSi layer was 12${\Omega}$/□ regardless of the thickness of the ${\alpha}$-Si and kept stable even after the additional annealing process. The thickness of the NiSi layer was 30 nm with excellent uniformity and the surface roughness was maintained under 2 nm after the annealing. Accordingly, our result implies that the low temperature Cat-CVD process with proposed films stack sequence may have more advantages than the conventional CVD process for nano scale NiSi applications.