• Transactions on Electrical and Electronic Materials
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• 제4권6호
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• pp.21-27
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• 2003

Methods of calculation of polarizers and splitters for visible spectra based on a multi-layer dielectric system are considered. Practical formulas for calculation are given. For example the cases of a splitter calculation when R$\_$s/ > 70% and R$\_$p/$\leq$ 30% or R$\_$s/=R$\_$p/ were considered. The formulas of the effective layers method are of practical use. The optical characteristics of calculated and fabricated polarizers and splitters for 650nm and 780nm wavelengths are presented.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.555-560
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• 2022

In this study, the insertion loss and phase delay according to the multi-layer structure radome parameters were analyzed using the boundary value solution approach, and the multi-layer structure and hexa mesh structures with low-loss electrical characteristics for the Ku-band transmission/reception frequency of 10.7 ~ 14.5 GHz were designed and manufactured. A hexa mesh was applied to minimize radio wave transmission and scattering, which lowered the transmittance refractive index according to the radio incident angle and minimized dielectric loss through high-density foam. Similar to the simulation result, the transmission loss obtained the gain in a specific receiving frequency band, and in the transmission frequency band, an excellent low loss characteristic was obtained with an insertion loss of 0.8dB or less. The results of this study can be used in radio transmission radomes of low-weight, low-cost end-system protection devices.

• E2M - 전기 전자와 첨단 소재
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• 제16권9호
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• pp.64.2-65
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• 2003

A 4 nm layer of ZrOx (targeted x-2) was deposited on an interfacial layer(IL) of native oxide (SiO, t∼1.2 nm) surface on 200 mm Si wafers by a manufacturable atomic layer chemical vapor deposition technique at 30$0^{\circ}C$. Some as-deposited layers were subjected to a post-deposition, rapid thermal annealing at $700^{\circ}C$ for 5 min in flowing oxygen at atmospheric pressure. The experimental x-ray diffraction, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and high-resolution parallel electron energy loss spectroscopy results showed that a multiphase and heterogeneous structure evolved, which we call the Zr-O/IL/Si stack. The as-deposited Zr-O layer was amorphous $ZrO_2$-rich Zr silicate containing about 15% by volume of embedded $ZrO_2$ nanocrystals, which transformed to a glass nanoceramic (with over 90% by volume of predominantly tetragonal-$ZrO_2$(t-$ZrO_2$) and monoclinic-$ZrO_2$(m-$ZrO_2$) nanocrystals) upon annealing. The formation of disordered amorphous regions within some of the nanocrystals, as well as crystalline regions with defects, probably gave rise to lattice strains and deformations. The interfacial layer (IL) was partitioned into an upper Si $o_2$-rich Zr silicate and the lower $SiO_{x}$. The latter was sub-toichiometric and the average oxidation state increased from Si0.86$^{＋}$ in $SiO_{0.43}$ (as-deposited) to Si1.32$^{＋}$ in $SiO_{0.66}$ (annealed). This high oxygen deficiency in $SiO_{x}$ indicative of the low mobility of oxidizing specie in the Zr-O layer. The stacks were characterized for their dielectric properties in the Pt/{Zr-O/IL}/Si metal oxide-semiconductor capacitor(MOSCAP) configuration. The measured equivalent oxide thickness (EOT) was not consistent with the calculated EOT using a bilayer model of $ZrO_2$ and $SiO_2$, and the capacitance in accumulation (and therefore, EOT and kZr-O) was frequency dispersive, trends well documented in literature. This behavior is qualitatively explained in terms of the multi-layer nanostructure and nanochemistry that evolves.ves.ves.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.464-467
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• 2005

In this paper, we present techniques to manufacture color electronic ink for multi-color electrophoretic display implementation. The charged color pigments have been prepared to have superior affinity for dielectric fluid. White $TiO_2$ nanoparticles were modified with poly(methyl methacrylate) copolymer for a microencapsulated electrophoretic display system, in order to reduce the density mismatch between nanoparticles and dielectric medium. These color balls and white pigment particle suspensions were microencapsulated through the typical microencapsulation technique. We fabricate the microcapsules to the single layer on flexible ITO substrate to test the multi-color electrophoretic display application.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.491-491
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• 2011

Transparent and flexible electronic devices that are light-weight, unbreakable, low power consumption, optically transparent, and mechanical flexible possibly have great potential in new applications of digital gadgets. Potential applications include transparent displays, heads-up display, sensor, and artificial skin. Recent reports on transparent and flexible field-effect transistors (tf-FETs) have focused on improving mechanical properties, optical transmittance, and performances. Most of tf-FET devices were fabricated with transparent oxide semiconductors which mechanical flexibility is limited. And, there have been no reports of transparent and flexible all-organic tf-FETs fabricated with organic semiconductor channel, gate dielectric, gate electrode, source/drain electrode, and encapsulation for sensor applications. We present the first demonstration of transparent, flexible all-organic sensor based on multifunctional organic FETs with organic semiconductor channel, gate dielectric, and electrodes having a capability of sensing infrared (IR) radiation and mechanical strain. The key component of our device design is to integrate the poly(vinylidene fluoride-triflouroethylene) (P(VDF-TrFE) co-polymer directly into transparent and flexible OFETs as a multi-functional dielectric layer, which has both piezoelectric and pyroelectric properties. The P(VDF-TrFE) co-polumer gate dielectric has a high sensitivity to the wavelength regime over 800 nm. In particular, wavelength variations of P(VDF-TrFE) molecules coincide with wavelength range of IR radiation from human body (7000 nm ~14000 nm) so that the devices are highly sensitive with IR radiation of human body. Devices were examined by measuring IR light response at different powers. After that, we continued to measure IR response under various bending radius. AC (alternating current) gate biasing method was used to separate the response of direct pyroelectric gate dielectric and other electrical parameters such as mobility, capacitance, and contact resistance. Experiment results demonstrate that the tf-OTFT with high sensitivity to IR radiation can be applied for IR sensors.

• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.1-7
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• 1999

MCM-D 기판에 수동소자를 내장시키는 공정을 개발하였다. MCM-D 기판은 Cu/감광성 BCB를 각각 금속배선 및 절연막 재료로 사용하였고, 금속배선은 Ti/cu를 각각 1000$\AA$/3000$\AA$으로 스퍼터한 후 fountain 방식으로 전기 도금하여 3 um Cu를 형성하였으며, BCB 층에 신뢰성있는 비아형성을 위하여 BCB의 공정특성과 $C_2F_6$를 사용한 플라즈마 cleaning영향을 AES로 분석하였다. 이 실험에서 제작한 MCM-D 기판은 절연막과 금속배선 층이 각각 5개, 4개 층으로 구성되는데 저항은 2번째 절연막 위에 thermal evaporator 방식으로 NiCr을 600$\AA$증착하여 시트저항이 21 $\Omega$/sq가 되게 형성하였고. 인덕터는 coplanar 구조로 3, 4번째 금속배선층에 형성하였으며, 커패시터는 절연막으로 PECVD $Si_3N_4$를 900$\AA$증착한 후 1, 2번째 금속배선층에 형성하여 88nF/$\textrm {cm}^2$의 커패시턴스를 얻었다. 이 공정은 PECVD $Si_3N_4$와 thermal evaporation NiCr 공정을 이용함으로써 기존의 반도체 공정을 이용하여 MCM-D 기판에 수동소자를 안정적으로 내장시킬 수 있었다.

• 한국재료학회지
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• 제17권4호
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• pp.185-191
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• 2007

The purpose of this study is to evaluate the thin fihn dielectric made of hybrid sol, which consist of barium titanate powder, polymeric sol and other polymers. This sol will be used dielectric applied to small, thin electric passive components such as MLCC(Multi Layer Ceramic Condenser), resister, inductor. This sol is composed of mixed fine barium titanate powder and polymeric sol including Ba, Ti-precursor, solvent, chelating agent, chemical reaction catalyst, the additive sols to improve fired densification and temperature reliability. First at all, we mixed hybrid sol to be dispersed and be stabilized by ball milling for 24hrs. By spin coating method, we makes thin film dielectric on the convectional green sheet for MLCC. After heat treatments, we analyzes the structure morphology, physical, electrical properties and X5R Temperature properties.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.176-176
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• 2010

One of the critical issues for applications of flexible organic thin film transistors (OTFTs) for flexible electronic systems is the electrical stabilities of the OTFT devices, including variation of the current on/off ratio (Ion/Ioff), leakage current, threshold voltage, and hysteresis under repetitive mechanical deformation. In particular, repetitive mechanical deformation accelerates the degradation of device performance at the ambient environment. In this work, electrical stability of the pentacene organic thin film transistors (OTFTs) employing multi-stack hybrid encapsulation layers was investigated under mechanical cyclic bending. Flexible bottom-gated pentacene-based OTFTs fabricated on flexible polyimide substrate with poly-4-vinyl phenol (PVP) dielectric as a gate dielectric were encapsulated by the plasma-deposited organic layer and atomic-layer-deposited inorganic layer. For cyclic bending experiment of flexible OTFTs, the devices were cyclically bent up to 105 times with 5mm bending radius. In the most of the devices after 105 times of bending cycles, the off-current of the OTFT with no encapsulation layers was quickly increased due to increases in the conductivity of the pentacene caused by doping effects from $O_2$ and $H_2O$ in the atmosphere, which leads to decrease in the Ion/Ioff and increase in the hysteresis. With encapsulation layers, however, the electrical stabilities of the OTFTs were improved significantly. In particular, the OTFTs with multi-stack hybrid encapsulation layer showed the best electrical stabilities up to the bending cycles of $10^5$ times compared to the devices with single organic encapsulation layer. Changes in electrical properties of cyclically bent OTFTs with encapsulation layers will be discussed in detail.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.632-635
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• 2008

본 논문에서는 LTCC 다층회로 기술을 이용하여 GSM/CDMA 대역을 분리하는 Diplexer를 설계하였다. Diplexer의 집적도를 높이기 위해 3차원 적층형 인덕터와 커패시터를 이용하여 설계되었다. Diplexer는 유전율 7.2인 총 6층의 LTCC 기판에 설계되었고, 설계 되어진 다이플렉서의 크기는 CB-CPW pad를 포함하여 $3,450{\times}4,000{\times}600{\mu}m^3$이다. GSM 대역의 통과 필터는 -0.23dB 이하의 삽입 손실과 -10dB 이하의 반사 손실, CDMA 대역의 통과 필터는 -0.53dB 이하의 삽입 손실과 -10dB 이하의 반사 손실의 특성을 보였다.

• 전자공학회논문지A
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• 제33A권7호
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• pp.149-155
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• 1996

A new technique wasdeveloped which obtains selectively the htick fully recessed oxidized porous silicon layer (OPSL) with good dielectric property. The porous silicon layer was ocnverted to thick fully recessed oxide (FRO) with 3-step (1${\mu}$m, 1.5${\mu}$m, 1.8${\mu}$m) by multi-step thermal oxidation (after 400$^{\circ}$C, 1 hour by dry oxidation, 700$^{\circ}$C, 1 hour and then 1100$^{\circ}$C, 1 hour by wet oxidation). The breakdwon field of the FRO was about 2.5MV/cm and the leakage current was several pA ~ 100 pA in the range of 0 of 90 pF. The progress of oxidation of a porous silicon layer was studied by examining the infrared abosrption spectra. The refractive index (1.51) of the fRO, which was measured by ellipsometer, was comparable to that of the thermally grown silicon dioxide (1.46). The etching rate (1600${\AA}$/min) of the FRO was also almost equal to that of the thermal oxide.