• E2M - 전기 전자와 첨단 소재
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• 제10권5호
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• pp.473-480
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• 1997

Surface passivation using glass powders results in good reliability for high voltage silicon power devices. In this paper Zinc borosilicate glass and Lead borosilicate glass were prepared for the purpose of passivating, and a deposition technique of glass films on the silicon surface by electrophoresis in which acetone is used as a suspension medium has been investigated. Their physical properties were compared using DTA, SEM, XRD, as a function of firing temperature, I can get the fine films of 22${\mu}{\textrm}{m}$ thickness with Lead borosilicate glass under 300 volts applied, 3 minutes and $700^{\circ}C$ firing temperature. Also I can get the fine films of 17${\mu}{\textrm}{m}$ thickness with Zinc borosilicate glass under same conditions. As a result of investigation of glass films from which glass layer was removed by placing it in HCl, it has been found that pre-firing and annealing play an important role to achieve uniform and fine glass deposition films. And also it was found that relative dielectric constant is independence of frequency.

• 한국전기전자재료학회논문지
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• 제25권2호
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• pp.125-128
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• 2012

We fabricated the electrolyte-insulator-semiconductor (EIS) devices with various high-k sensing membranes to realize a high quality pH sensor. The sensing properties of each high-k dielectric material were compared with those of conventional $SiO_2$ (O) and $SiO_2/Si_3N_4$ (ON) membranes. As a result, the high-k sensing membranes demonstrated better sensitivity and stability than the O and ON membranes. Especially, the $SiO_2/HfO_2$ (OH) stacked layer showed a high sensitivity and the $SiO_2/Al_2O_3$ (OA) stacked layer exhibited an excellent chemical stability. In conclusion, the high-k sensing membranes are expected to have excellent operating characteristics in terms of sensitivity and chemical stability for the biosensor application.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.285-288
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• 1997

Generally the high dielectric films, such as PZT(Pb(Z $r^{1-x}$ $Ti_{x}$ ) $O_3$) and BST(B $a_{l-x}$S $r_{x}$ Ti $O_3$) have been formed on the Pt thin films. However it is generally known that the dry etching of Pt is difficult because of its chemical stability. So, the dry etching of Pt remains at the preliminary work. Therefore, in this study, Pt etching mechanism was investigated with Ar/C $l_2$gas plasma by using XPS(X-ray photoelectron spectroscopy) and QMS(Quadrupole mass spectrometry). Ion current density was measured with Ar/C $l_2$gas plasma by using single Langmuir probe. XPS results shoved that the atomic % of Cl element on the etched Pt sample increased with increasing Ar/(Ar+C $l_2$). And QMS results showed that the increase of Ar partial pressure in the plasma resulted in the improvement of C $l_2$dissociation and Cl redical formation and simultaniously the increase of ion bombardment effects.s.s.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.344-345
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• 2006

In this study, in order to develop low temperature sintering piezoelectric transformer, $(Pb_{0.99-x}Ca_xSr_{0.01})Ti_{0.96}(Mn_{1/3}Sb_{2/3})_{0.04}O_3$ ceramic systems were fabricated using $Na_2CO_3-Li_2CO_3$ as sintering aids and investigated with the amount of Ca substitution. The piezoelectric transformer requires high electromechanical coupling factor $k_t$ and high mechanical quality factor $Q_{mt}$ for generating high output power At the ($PbCaSr)Ti(MnSb)O_3$ ceramics with 24mol% Ca substitution sintered at $900^{\circ}C$, electromechanical coupling factor $k_t$ and mechanical quality factor $Q_{mt}$ showed the optimal values of 0.504 and 1655 respectively, for thickness vibration mode multilayer piezoelectric transformer application.

• Advances in nano research
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• 제9권1호
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• pp.1-13
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• 2020

In this work, the electrical potential (EP) technique with an artificial neural networks (ANNs) for monitoring of nanostructures are used for the first time. This study employs an expert system to identify size and localize hidden nano-delamination (N.Del) inside layers of nano-pipe (N.P) manufactured from Basalt Fiber Reinforced Polymer (BFRP) laminate composite by using low-cost monitoring method of electrical potential (EP) technique with an artificial neural networks (ANNs), which are combined to decrease detection effort to discern N.Del location/size inside the N.P layers, with high accuracy, simple and low-cost. The dielectric properties of the N.P material are measured before and after N.Del introduced using arrays of electrical contacts and the variation in capacitance values, capacitance change and node potential distribution are analyzed. Using these changes in electrical potential due to N.Del, a finite element (FE) simulation model for N.Del location/size detection is generated by ANSYS and MATLAB, which are combined to simulate sensor characteristic, therefore, FE analyses are employed to make sets of data for the learning of the ANNs. The method is applied for the N.Del monitoring, to minimize the number of FE analysis in order to keep the cost and save the time of the assessment to a minimum. The FE results are in excellent agreement with an ANN and the experimental results available in the literature, thus validating the accuracy and reliability of the proposed technique.

• E2M - 전기 전자와 첨단 소재
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• 제9권2호
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• pp.146-151
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• 1996

PZT powders were prepared by the molten salt synthesis method. The porous PZT ceramics were made from a mixture of PZT and polyvinylalcohol(PVA) by BURPS(Bumout Plastic Sphere) technique. The 3-3 type composites were fabricated by impregnating an sintered porous PZT ceramics with various polymer matrices. The relative permittivity of 3-3 type composite specimens was shown 860-1,100 smaller than that of solid PZT ceramics(2,100), and the dissipation factors of composite specimens were about 0.02 to 0.03. The piezoelectric coefficient d$_{33}$ of composite specimens(285-328*10$^{12}$ C/N) was comparable with that of single phase PZT specimens(364*10$^{-12}$ C/N). The thickness mode coupling factor k$_{t}$(O.5-0.6) of composite specimens was comparable with that of single phase PZT specimens(k$_{t}$-0.7), and the mechanical quality factor of composite specimens was smaller than 10, and thus these 3-3 type composite specimens would be believed as a good candidates for broad band transducer applications.ons.

• 마이크로전자및패키징학회지
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• 제11권3호
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• pp.63-70
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• 2004

The structural, electrical properties of $(Ba, Sr)TiO_3[BSTO]/RuO_2$ thin films were examined by the addition of amorphous BSTO layer between crystlline BSTO film and $RuO_2$ substrate. We prepared BSTO films with double-layered structure, that is, amorphous layers deposited at $60^{\circ}C$ and crystalline films. Crystalline films were prepared at 550 on amorphous BSTO layer. The thickness of the amorphous layers was varied from 0 to 170 nm. During the deposition of crystalline films, the crystallization of the amorphous layers occurred and the structure was changed to circular while crystalline BSTO films showed columnar structure. Due to insufficient annealing effect, amorphous BSTO phase was observed when the thickness of the amorphous layers exceeded 30 nm. Amorphous BSTO layer could also prevent the formation of oxygen deficient region in $RuO_2$ surface. Leakage current of total BSTO films decreased with increasing amorphous layer thickness due to structural modifications. Dielectric constant showed maxi-mum value of 343 when amorphous layer thickness was 30 nm at which the improvement by grain growth and the degradation by amorphous phase were balanced.

• 조명전기설비학회논문지
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• 제14권3호
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• pp.38-42
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• 2000

플라즈마 중합박막은 내정전 플라즈마 중합장치에 의해서 제조되었다. 중칙률을 4O[W]에서 100[W] 사이에서 최대값을 나타내었다. ESCA 분석에샤는 285.4와 285.5[eV]에서 -CH2, -C-를 나타내는 피크들을 보였다. 무시할 수 없는 양으로 산소와 그룹화 되어 있는 532.8[eV]에서의 C-O와 533.8[eV)에서의 C-O[C/O=8]를 확인하였다. ESR 분석에서 강한 진폭이 나타나는 곡선은 매우 약한 방전전력에 영향을 받은 포화상태를 나타낸다. 알림기를 함유한 -CH-CH=CH- 구조로 사료된다. 제조된 플라즈마 중합박막은 100[Hz]~200[kHz]의 주파수에서 비유전율이 3,5정도를 보이고 유전정접은 0.08의 낮은 값올 냐타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.305-309
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• 2002

We have successfully fabricated a Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure using Bi$\sub$4-x/La$\sub$x/Ti$_3$O$\sub$12/ (BLT) ferroelectric thin film and SiO$_2$/Nitride/SiO$_2$ (ONO) stacked buffer layers for single transistor type ferroelectric nonvolatile memory applications. BLT films were deposited on 15 nm-thick ONO buffer layer by sol-gel spin-coating. The dielectric constant and the leakage current density of prepared ONO film were measured to be 5.6 and 1.0 x 10$\^$-8/ A/$\textrm{cm}^2$ at 2MV/cm, respectively, It was interesting to note that the crystallographic orientations of BLT thin films were strongly effected by pre-bake temperatures. X-ray diffraction patterns showed that (117) crystallites were mainly detected in the BLT film if pre-baked below 400$^{\circ}C$. Whereas, for the films pre-baked above 500$^{\circ}C$, the crystallites with preferred c-axis orientation were mainly detected. From the C-V measurement of the MFIS capacitor with c-axis oriented BLT films, the memory window of 0.6 V was obtained at a voltage sweep of ${\pm}$8 V, which evidently reflects the ferroelectric memory effect of a BLT/ONO/Si structure.

• E2M - 전기 전자와 첨단 소재
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• 제9권6호
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• pp.551-557
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• 1996

To decrease the hysteresis of electric field induced strain, $Y_{2}$ $O_{3}$ dopant of which amount is 0-0.8wt% was added to the (P $b_{0.73}$B $a_{0.27}$)(Z $r_{0}$ 75/ $Ti_{0.25}$) $O_{3}$ ceramics. Electromechanical coupling coefficients of the specimen with 0.1 Wt% $Y_{2}$ $O_{3}$ were $k_{p}$=26.9% and $k_{31}$ =20.4%, which exhibited the maximum value at the constant bias electric field of 10 kV/cm. At the same $Y_{2}$ $O_{3}$ addition amount, electric field piezoelectric constant ( $d_{3l}$) and strain(.DELTA.l/l) showed the maximum values of 139.6*10$^{-12}$ [C/N] and 126*10$^{-6}$ .DELTA. l/l respectively at 10 kV/cm electric field. And the hysteresis of strain showed the minimum value of 17.5%. So, we propose that it is possible to apply PBZT system with $Y_{2}$ $O_{3}$ dopant to the electrostrictive actuator.r.r.