• 한국결정성장학회지
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• 제25권6호
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• pp.239-244
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• 2015

에어로졸 증착법에 의해 실리콘 기판위에 $10{\sim}20{\mu}m$의 두께를 가진 PZT 후막을 제조한 후 $700^{\circ}C$에서 어닐링처리하였다. PZT 분말에 의해 제조된 막은 임피던스 분석기(impedance analyzer)와 쇼여-타워 서킷(Sawyer-Tower circuit)으로 분석하였다. PZT 분말은 통상적인 고상반응법 및 솔-젤 법으로 준비되었다. 고상반응법으로 만들어진 분말을 사용한 $10{\mu}m$ 두께 PZT 막의 잔류분극, 항전계 및 유전상수는 각각 $20{\mu}C/cm^2$, 30 kV/cm 그리고 1320이었다. 한편 솔-젤 법으로 제조된 분말을 사용한 경우의 유전상수는 635로 비교적 낮은 값을 나타낸다. 이는 어닐링시 생기는 발생하는 유기물에 의한 기공의 존재 때문이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집
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• pp.27-32
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• 2004

Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuir-films. MDC flowing across monolayers is analyzed using a rod-like molecular model. A method for determining the dielectric relaxation time ${\tau}$ of floating 'monolayers on the water surface is presented. MDC floing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time ${\tau}$ of monolayers in the isotropic polar orientational phase is determined using a liner relationship between the monolayer compression speed a and the molecular area Am. Compression speed a was about 30,40,50mm/min. LB layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film.The physicochemical properties of the LB films were examined by UV absorption spectrum, SEM and AFM. The structure of manufactured device is Au/Arachidic acid/Al, the number of accumulated layers are 3~9. Also, we then examined of the MIM device by means of I-V characteristic of the device is measured from -3 to +3[V]. The insulation property of a thin film is better as the distance between electrodes is larger.

• 한국전기전자재료학회논문지
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• 제20권8호
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• pp.680-684
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• 2007

In this study, we investigated the effects of structural and electrical properties of $(Ba_{0.6},\;Sr_{0.3},\;Ca_{0.1})TiO_3$ thick films with variation $Dy_2O_3$ contents. $(Ba_{0.6},\;Sr_{0.3},\;Ca_{0.1})TiO_3$ powders, prepared by the sol-gel method, were mixed organic vehicle. The BSCT thick films doped with 0.1, 0.3, 0.5, 0.7 mol% $Dy_2O_3$ were fabricated by the screen-printing techniques on the alumina substrates and the structural and dielectric properties were investigated with variation of $Dy_2O_3$ doping contents. All BSCT thick films were sintered at $1420^{\circ}C$, for 2hr. In the TG-DTA analysis, the formation of the polycrystalline perovskite phase was observed at around $670 ^{\circ}C$. In the XRD analysis, all BSCT thick films showed the cubic perovskite structure. The average thickness of BSCT thick films was approximately $65{\mu}m$. The Curie temperature decreased with increasing $Dy_2O_3$ amount. The relative dielectric constant and dielectric loss of BSCT thick films doped with $Dy_2O_3$ 0.1 mol% were 6267 and 2.6 %, respectively.

• 한국전기전자재료학회논문지
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• 제16권3호
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• pp.247-252
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• 2003

In this paper, we made four types of metal particle $Al_2$O$_3$ barrier reactors with and without dielectric of BaTiO$_3$ between metal particle and $Al_2$O$_3$ barrier to investigate NOx removal characteristic and the effect of dielectric on Nox removal. And Nox removal rate is measured when sludge pellets are put at down stream of plasma reactor. Nox removal rate in the reactor with $Al_2$O$_3$ barrier is much better than that in the reactor without $Al_2$O$_3$ barrier, Nox removal rate is not so good in metal particle-Al$_2$O$_3$ barrier reactor with BaTiO$_3$ between metal particle and $Al_2$O$_3$ barrier, however, Nox removal rate is about 40% in metal particle-Al$_2$O$_3$ barrier reactor with TiO$_2$. The most of NO is conversed to NO$_2$ in these kind of reactor. When sludge pellets are put at down stream of plasma reactor, Nox removal rate is greatly improved up to 90%. It indicates that sludge pellets have great effect on the NO$_2$ removal and the improvement of Nox removal rate, however, dielectric materials between metal particle and $Al_2$O$_3$ barrier have not effect. Organic materials included in sludge may react with NO$_2$ and ozone so that Nox removal rate is greatly improved.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.96-96
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• 2007

Low voltage organic TFTs (OTFTs) and ZnO based TFTs (<5V), utilizing room temperature deposited $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin films were recently reported, pointing to high-k gate insulators as a promising route for realizing low voltage operating flexible electronics. $Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7$ (BZN) thin film is one of the most promising materials for gate insulator because of its large dielectric constant (~60) at room temperature. However their tendency to suffer from relatively high leakage current at low electric field (>0.3MV/cm) hinder the application of BZN thin films for gate insulator. In order to improve leakage current characteristics of BZN thin film, we mixed 30mol% MgO with 70mol% BZN and their dielectric and electric properties were characterized. We fabricated field-effect transistors with transparent oxide semiconductor ZnO serving as the electron channel and high-k $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ as the gate insulator. The devices exhibited low operation voltages (<4V) due to high capacitance of the $(Bi_{1.5}Zn_{1.0}Nb_{1.5}O_7)_{0.7}(MgO)_{0.3}$ dielectric.

• 상하수도학회지
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• 제34권1호
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• pp.75-83
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• 2020

This study investigated the degradation characteristics and biodegradability of phenol, refractory organic matters, by injecting MgO and CaO-known to be catalyst materials for the ozonation process-into a Dielectric Barrier Discharge (DBD) plasma. MgO and CaO were injected at 0, 0.5, 1.0, and 2 g/L, and the pH was not adjusted separately to examine the optimal injection amounts of MgO and CaO. When MgO and CaO were injected, the phenol decomposition rate was increased, and the reaction time was found to decrease by 2.1 to 2.6 times. In addition, during CaO injection, intermediate products combined with Ca²⁺ to cause precipitation, which increased the COD (chemical oxygen demand) removal rate by approximately 2.4 times. The biodegradability of plasma treated water increased with increase in the phenol decomposition rate and increased as the amount of the generated intermediate products increased. The biodegradability was the highest in the plasma reaction with MgO injection as compared to when the DBD plasma pH was adjusted. Thus, it was found that a DBD plasma can degrade non-biodegradable phenols and increase biodegradability.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2003년도 추계학술발표회초록집
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• pp.119-119
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• 2003

Plasma polymerized organic thin films were deposited on Si(100) glass and Copper substrates at 25 ∼ 100 $^{\circ}C$ using cyclohexane and ethylcyclohexane precursors by PECVD method. In order to compare physical and electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 20∼50 W and deposition temperature on both corrosion protection efficiency and physical properties were studied. We found that the corrosion protection efficiency (P$\_$k/), which is one of the important factors for corrosion protection in the interlayer dielectrics of microelectronic devices application, was increased with increasing RF power. The highest P$\_$k/ value of plasma polymerized ethylcyclohexane film (92.1% at 50 W) was higher than that of the plasma polymerized cyclohexane film (85.26% at 50 W), indicating inhibition of oxygen reduction. Impedance analyzer was utilized for the determination of I-V curve for leakage current density and C-V for dielectric constants. To obtain C-V curve, we used a MIM structure of metal(Al)-insulator(plasma polymerized thin film)-metal(Pt) structure. Al as the electrode was evaporated on the ethylcyclohexane films that grew on Pt coated silicon substrates, and the dielectric constants of the as-grown films were then calculated from C-V data measured at 1㎒. From the electrical property measurements such as I-V ana C-V characteristics, the minimum dielectric constant and the best leakage current of ethylcyclohexane thin films were obtained to be about 3.11 and 5 ${\times}$ 10$\^$-12/ A/$\textrm{cm}^2$ and cyclohexane thin films were obtained to be about 2.3 and 8 ${\times}$ 10$\^$-12/ A/$\textrm{cm}^2$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.77-77
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• 2000

Titanium oxide (TiO2) thin films have valuable properties such as a high refractive index, excellent transmittance in the visible and near-IR frequency, and high chemical stability. Therefore it is extensively used in anti-reflection coating, sensor, and photocatalysis as electrical and optical applications. Specially, TiO2 have a high dielectric constant of 180 along the c axis and 90 along the a axis, so it is highlighted in fabricating dielectric capacitors in micro electronic devices. A variety of methods have been used to produce patterned self-assembled monolayers (SAMs), including microcontact printing ($\mu$CP), UV-photolithotgraphy, e-beam lithography, scanned-probe based micro-machining, and atom-lithography. Above all, thin film fabrication on $\mu$CP modified surface is a potentially low-cost, high-throughput method, because it does not require expensive photolithographic equipment, and it produce micrometer scale patterns in thin film materials. The patterned SAMs were used as thin resists, to transfer patterns onto thin films either by chemical etching or by selective deposition. In this study, we deposited TiO2 thin films on Si (1000 substrateds using titanium (IV) isopropoxide ([Ti(O(C3H7)4)] ; TIP as a single molecular precursor at deposition temperature in the range of 300-$700^{\circ}C$ without any carrier and bubbler gas. Crack-free, highly oriented TiO2 polycrystalline thin films with anatase phase and stoichimetric ratio of Ti and O were successfully deposited on Si(100) at temperature as low as 50$0^{\circ}C$. XRD and TED data showed that below 50$0^{\circ}C$, the TiO2 thin films were dominantly grown on Si(100) surfaces in the [211] direction, whereas with increasing the deposition temperature to $700^{\circ}C$, the main films growth direction was changed to be [200]. Two distinct growth behaviors were observed from the Arhenius plots. In addition to deposition of THe TiO2 thin films on Si(100) substrates, patterning of TiO2 thin films was also performed at grown temperature in the range of 300-50$0^{\circ}C$ by MOCVD onto the Si(100) substrates of which surface was modified by organic thin film template. The organic thin film of SAm is obtained by the $\mu$CP method. Alpha-step profile and optical microscope images showed that the boundaries between SAMs areas and selectively deposited TiO2 thin film areas are very definite and sharp. Capacitance - Voltage measurements made on TiO2 films gave a dielectric constant of 29, suggesting a possibility of electronic material applications.

• 공업화학
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• 제24권3호
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• pp.219-226
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• 2013

차세대 전자 디스플레이 관련 제품의 휴대편리성, 유연성, 경량화, 대형화 등의 요구조건을 확보할 수 있는 유기반도체 소재기반 소프트 일렉트로닉스에 많은 관심이 모아지고 있다. 소프트 일렉트로닉스의 응용분야로는 전자 신문, 전자 책, 스마트카드, RFID 태그, 태양전지, 휴대용 컴퓨터, 센서, 메모리 등이 있으며, 핵심소자는 유기 전계효과 트랜지스터(organic field-effect transistor, OFET)이다. OFET의 고성능화를 위해서는 유기반도체, 절연체, 전극 구성소재들이 최적화 구조를 형성하도록 적층되어야 한다. 필름형성화 과정에서 대부분의 유기반도체 소재는 결합력이 약한 van der Waals 결합으로 자기조립 결정구조를 형성하므로, 이들의 결정성 필름구조는 주위 환경(공정변수 및 기질특성)에 의해 크게 달라진다. 특히 기질의 표면 에너지(surface energy) 및 표면 거칠기(surface roughness)에 따라 유기반도체 박막 내 결정 구조 및 배향 등은 크게 달라져, OFET의 전기적 특성에 큰 차이를 미친다. 유기친화적 절연층 소재 및 표면개질화는 전하이동에 유리하도록 용액 및 증착공정 유기반도체 박막의 결정구조 및 배향을 유도시켜 OFET의 전기적 성능을 향상시킬 수 있다.

• 한국환경과학회지
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• 제23권9호
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• pp.1627-1634
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• 2014

Odor control technology include absorption, adsorption, incineration and biological treatments. But, most of processes have some problems such as secondary organic acids discharge at the final odor treatment facility. In order to solve the problems for effective treatment of organic acids in odor, it is necessary to develop a new type advanced odor control technology. Some of the technology are plasma only process and plasma hybrid process as key process of the advanced technology. In this study, odor removal performance was compared DBD(Dielectric Barrier Discharge)plasma process with PCHP(plasma catalysis hybrid process) by gaseous ammonia, formaldehyde and acetic acid. Plasma only process by acetic acid obtained higher treatment efficiency above 90%, and PCHP reached its efficiency up to 96%. Acetic acid is relatively easy pollutant to control its concentration other than sulfur and nitrogen odor compounds, because it has tendency to react with water quickly. To test of the performance of DBD plasma process by applied voltage, the tests were conducted to find the dependence of experimental conditions of the applied voltage at 13 kV and 15 kV separately. With an applied voltage at 15 kV, the treatment efficiency was achieved to more higher than 13 kV from 83% to 99% on ammonia, formaldehyde and acetic acid. It seems to the odor treatment efficiency depends on the applied voltage, temperature, humidity and chemical bonding of odors.