New material design has obtained tremendous attention in material science community as the performance of new materials, especially in nano length scale, could be greatly improved to applied in modern industry. In certain conditions limiting experimental synthesis of these new materials, new approach by computer simulation has been proposed to be applied, being able to save time and cost. Recent development of computer systems with high speed, large memory, and parallel algorithms enables to analyze individual atoms using first principle calculation to predict quantum phenomena. Beyond the quantum level calculations, mesoscopic scale and continuum limit can be addressed either individually or together as a multi-scale approach. In this article, we introduced current endeavors on material design using analytical theory and computer simulations in multi-length scales and on multi-physical properties. Some of the physical phenomena was shown to be interconnected via a cross-link rule called ``cross-property relation``. It is suggested that the computer simulation approach by multi-physics analysis can be efficiently applied to design new materials for multi-functional characteristics.

A marvellous solar cell technology system based on organometal halide perovskites has recently shown an unprecedented progress in power conversion efficiency (PCE); the certified one of 17.9% and unconfirmed of 19.3%, as well as the estimated electricity with a generating cost lower than the half of conventional methods based on fossil fuels. In this report the present status of stability with regards to moisture, ambient temperature, ultraviolet and lead toxicity as well as the key technological developments for the early commercialization are covered. Comprehensive understanding of material science for perovskitesis required, together with complete encapsulation technologies beyond those for OLEDs, in order to ensure a20-year-longer-than lifetime of PSCs (perovskite solar cells) and the stability according to the IEC 61646damp heat test standard, which will result in the replacement of silicon solar cells with PSCs.

In this paper, we investigated the hot carrier reliability of two kinds of device with low threshold voltage (LVT) and regular threshold voltage (RVT) in 65 nm CMOS technology. Contrary to the previous report that devices beyond 0.18 μm CMOS technology is dominated by channel hot carrier(CHC) stress rather than drain avalanche hot carrier(DAHC) stress, both of LVT and RVT devices showed that their degradation is dominated by DAHC stress. It is also shown that in case of LVT devices, contribution of interface trap generation to the device degradation is greater under DAHC stress than CHC stress, while there is little difference for RVT devices.

In this study, in order to develop the capacitor composition ceramics with the good dielectric properties, (Ba1-xCax)(Ti0.85Zr0.12Sn0.03)O3 (abbreviated as BCTZ) ceramics were prepared by the conventional solid-state reaction method. The effects of Ca substitution on the microstructure and dielectric properties was investigated. The X-ray diffraction patterns demonstrated that all the specimens showed perovskitephase, and secondary phases are indicated in the measurement range of X-ray diffraction. Also, all the specimens indicated an rhombohedron phase structure. It was identified from the X-ray diffraction patterns that the secondary phase formed in grain boundaries and then decreased the dielectric properties. For all the specimens, observed one peak was tetragonal cubic phase transition temperature(TC),which is located in the vicinity of room temperature.

Bi0.5+x(Na0.78K0.22)0.5-3xTiO3 ceramics with an excess Bi3+ and a deficiency of Na+ and K+ were synthesized by a conventional solid state reaction method. The structure and morphology ofBi0.5+x(Na0.78K0.22)0.5-3xTiO3 ceramics were characterized by X-ray diffraction and field emission scanning electron microscopy. The electric polarization and mechanical strain induced by external electric field, and the temperature dependence of dielectric constant were investigated. These results demonstrated that anergodic relax or phase can be induced by controls of the mole ratio of Bi3+, Na+ and K+. A phase boundary between non-ergodic and ergodic relaxor phases can be observed at ambient temperature. Theergodic relaxor phase can be transferred to the ferroelectric phase by application of the electric field. The stability of the induced ferroelectric phases strongly depends on the mole ratio of Bi3+, Na+ and K+. The maximum strain of 0.31% was observed in Bi0.51(Na0.78K0.22)0.47TiO3 ceramics sintered at 1,150℃ for 2 h.

Spinel thin films were prepared by the spin spray technique to develop new thermal imaging materials annealed at low temperature for uncooled microbolometer applications. The spinel thin films were deposited from [(Ni0.30Co0.33Mn0.37)1-xCux]3O4 (0.1≤x≤0.2) solutions and then annealed at 400℃ for 1 h inargon. Effects of Cu content (x) and deposition time on the electrical properties of the annealed films were investigated. With increasing deposition time, the resistivity of the annealed films increased. For the annealed films deposited for 1 min, the resistivity of x=0.15 films was lower than that of x=0.1 films due to the different grain sizes. The high temperature coefficient of resistance (TCR) of the annealed films could be obtained at temperature below 50℃. Typically, the resistivity of 127 Ω·cm and TCR of -5.69%/Kat 30℃ were obtained for x=0.1 films with deposition time of 1 min annealed at 400℃ for 1 h in argon.

Aluminum nitride (AlN) thin film and TiN film as a buffer layer were deposited on INCONEL600 substrate by reactive RF magnetron sputtering at room temperature(R.T.) under 25∼75% N2/Aratmosphere. The as-deposited AlN films at 25∼50% N2/Ar showed a polycrystalline phase of hexagonal AlN, and an amorphous phase. The peak of AlN (002) plane, which was determinant on a performance of piezoelectric transducer, became strong with increasing the N2/Ar ratio. Any change in the preferential orientation of the as-deposited AlN films was not observed within our N2 concentration range. The piezoelectric sensing properties of AlN module were performed using pressure-voltage measurement system. The output signal voltage of AlN module showed a linear behavior between 20∼80 mV in 1∼10MPa range, and the pressure-sensing sensitivity was calculated as 3.6 mV/MPa.

TiNOx multi-layer thin films on aluminum substrates were prepared by DC reactive magnetron sputtering method. 4 multi-layers of TiO2/TiNOx(LMVF)/TiNOx(HMVF)/Ti/substrate have been prepared with ratio of Ar and (N2+O2) gas mixture. TiO2 of top layer is anti-reflection layer on double TiNOx(LMVF)/TiNOx(HMVF) layers and Ti metal of infrared reflection layer. In this study, thecrystallinity and surface properties of TiNOx thin films were estimated by X-ray diffraction(XRD) and field emission scanning electron microscopy(FE-SEM), respectively. The grain size of TiNOx thin films shows to increase with increasing sputtering power. The composition of thin films has been investigated using electron probe microanalysis(EPMA). The optical properties with wavelength spectrum were recorded by UV-Vis-NIR spectrophotometry at a range of 200∼1,500 nm. The TiNOx multi-layer films show the excellent optical performance beyond 9% of reflectance in those ranges wavelength.

[(Co1-xCux)0.2(Ni0.3Mn0.7)0.8]3O4 (0≤x≤1) thin films prepared by metal organic decomposition process were fabricated on SiN/Si substrate for infrared sensor application. Their structural and electrical properties were investigated with variation of Cu dopant. The [(Co1-xCux)0.2(Ni0.3Mn0.7)0.8]3O4 (CCNMO) film annealed at500℃ exhibited a dense microstructure and a homogeneous crystal structure with a cubic spinel phase. Theircrystallinity was further enhanced with increasing doped Cu amount. The 120 nm-thick CCNMO (x=0.6) thin film had a low resistivity of 53 Ω·cm at room temperature while the Co-free film (x=1) showed a significantly decreased resistivity of 5.9 Ω·cm. Furthermore, the negative temperature coefficient of resistance(NTCR) characteristics were lower than -2%/℃ for all the specimens with x≥0.6. These results imply that the CCNMO (x≥0.6) thin films are a good candidate material for infrared sensor application.

One-dimensional (1D) photonic crystals (PCs) were prepared by TeOx(2＜x＜3)/SiO2 with thedifference refractive index, and fabricated by sputtering technique from a TeO2 and SiO2 target. TheTeOx(2＜x＜3) layers were fabricated by using the sputtering gas ratio (Ar:O2=40:10). A 10-pair TeOx(2＜x＜3)/SiO2 1D PCs were fabricated with the structure parameters of filling factor=0.5185, and period=410nm. The properties of 1D PCs with and without a defect layer were evaluated by UV-VIS-NIR. Anormal mode 1D PC have a photonic band gap (PBG) in the near infrared (NIR) region from 1,203 to1,421 nm. In the case of 1D PC containing a defect layer, a defect level appears at 1,291 nm. Themeasured transmittance (T) spectra are nearly corresponding to calculated results. After He-Cd laserexposure, the defect level is shifted from 1,291 nm to 1,304 nm.

Novel materials of Zn(HPB)2 and Ir-complexes were respectively synthesized as blue or redemitting material. White Organic Light Emitting Diodes (OLED) were fabricated by using Zn(HPB)2 for ablue emitting layer, Ir-complexes for a red emitting layer and Alq3 for a green emitting layer. White OLED was fabricated by using double emitting layers of Zn(HPB)2 and Alq3:Ir-complexes, and hole blocking layer of BCP. We also varied the thickness of BCP. When the thickness of BCP layer was 5nm, white emission was achieved. We obtained a maximum luminance of 3,500 cd/m2. The CIE coordinates was (0.375, 0.331). From this study, we could propose that the hybrid structure is efficient in lighting application of white OLED by improvement of color purity.

It found that the maximum temperature of the arc discharge occurred on the Silicone rubber sample significantly decreased with increasing the reinforcing agent. It was confirmed that the current value decreased with increasing the aluminium trihyd rate(Al(OH)3) and the current value increased with reducing the primary resistance over time. Regarding these results, may be it is because the degradation due to the electro-conductive carbonization was improved and the properties of dielectric breakdown was reduced by the flame retardant reinforcing agent. It found that the electro-conductive carbonized road has not happened by increasing the flame retardant reinforcing agent. Regarding to the arc discharge, this study show that the arc arising near the lower electrode of sample has disappeared.

The characteristics of dielectric constant and tanδ of low viscosity silicone oils with changing degree of polymerization were investigated. The result shows dipole loss mechanism at low temperature range. The dielectric loss in the range of low frequencies are predominantly of ionic nature with temperature increase. The peak of dielectric loss is the detrapping of the electrons which is were trapped in the localized level of the silicone oils at the frequency of 30 kHz. The increase of ionic conduction is attributed to the presence of ionizable oxidation products and their increased dissociation feature. The activation energy △H and dipole moment μd were increased whit increasing degree of polymerization.

BaTiO3 nano powder can be synthesized by hydrate salt method at 120℃ in air. Decreasing the thickness of thick film, the nano dielectric particle is needed in electronic ceramics. However, the synthesis of BaTiO3 nano particle at low temperature in air and their mechanism were not reported enough. And ultrasonic treatment can be tried because of low temperature process in air. Therefore, in this study, the BaTiO3 nano powder was synthesised with the synthesis time and ultrasonic treatment at120oC in air. In the synthesis process, the effects of process were evaluated. From the experimental observation, the synthesis mechanism was proposed. The homogeneous BaTiO3 particle was synthesized by KOH salt solution at 120℃ for 1hour. It was conformed that the ultrasonic treatment effected on theincrease of synthesis rate. After cutting the salt powder using FIB, BaTiO3 nano particles observed homogeneously in the cross-section of the salt particle.

In this paper, we designed and fabricated electromagnetic induction based scaffold type energy harvester. For energy harvesting, mechanical energy of vertical motion is transferred to rotational energy using rack gear and multiplying gear was used to maximize energy transfer. To optimize design parameters, physical structure of energy harvester was modeled using finite element method. The effect of multiplying gear ratio and frequency levels of applied mechanical energy on energy generation efficiency are analyzed by computer simulation and experimental test. Experimental results showed that maximum 25.36 W of electric power can be achieved at the frequency of 2 Hz and 1:77 of gear ratio with only 5 mm of vertical changes on scaffold structure.

Energy problem has been issued in worldwide because fossil fuel has being almost exhausted. A lot of renewable energy have been received attention to replace the energy from fossil fuel. Among them, piezoelectric energy harvester is one of excellent candidates. In general, micro scaled small sized energy harvesters were usually based on the lithography process. However, these lithography process require complicated process and high cost. In this paper, a new process has been proposed for micro-scaled piezoelectric energy harvester. 0.2Pb(Mg1/3Nb2/3)O3-0.8Pb(Zr0.52Ti0.48)O3 composition was used as piezoelectric material due to excellent piezoelectric properties and also can be easily prepared by mixedoxide method.

In solid oxide fuel cell system, yttria-stabilized zirconia is generally adopted as the electrolyte, which has high strength and superior oxygen ion conductivity, and the air electrode and the fuel electrode are attached to this. Recently, new structure of ``layered planar SOFC module`` was suggested to solve there liability problem due to the high temperature stability of a sealing agent and a binding material. In this study to materialize the air electrode in a layered planar SOFC module, the LSM ink was coated to form homogeneous electrode in the channel after the ink preparation. As the porosity control agent, PMMA oractive carbon powder was adopted with use of a commercial dispersant in ethanol. The optimal amounts of both the porosity control agents and the dispersant were determined. Four (4) vol% of the dispersant for the LSM-PMMA case and 15 vol% for LSM-carbon powder showed the lowest viscosities respectively to indicate the best dispersed states of the slurries. With PMMA and carbon powder, sintered LSM ink shows the relatively homogeneous distributions of pores and with increases of the agents, the porosities increased in both cases. From this, it can be thought that the amount of the PMMA or carbon powder could be used to control the porosity of the LSM ink.

Efficiency of crystalline Si solar cell can be maximized as minimizing optical loss through antireflection texturing with inverted pyramids. Even if cost-competitive, soft lithography can be employed instead of photolithography for the purpose, some limitations still remain to apply the soft lithography directly to as-received solar grade wafer with a bunch of micro trenches on surface. Therefore, it is needed to develop a low-cost, effective planarization process and evaluate its output to be applicable to patterning process with PDMS stamp. In this study new surface planarization process is proposed and the change of micro scale trenches on the surface as a function of etching time is observed. Also, the effect of trenches on pattern quality by soft lithography is investigated using FEM structural analysis. In conclusion it is clear that the geometry and shape of trenches would be basic considerations for soft lithography application to low quality wafer.

It has been confirmed that the inner defect of transformer and the perfect diagnosis for aging are closely related to safe electric power transmission system and that the detection of accident and diagnosis technique turn out to be very important issues. Since electric power machinery consists of various kinds of components, however, it is very difficult to make a diagnosis for aging by one parameter. Thus, diagnosis for aging is feasible only through the combination of various parameters. Recently, various expert systems have been developed and applied to diagnosis for aging, but they are not yet reliable enough to apply to the real system. In this paper, XLPE which is ultra high voltage cableinsulator material were chosen to investigate the influence of void on insulator material using partial discharge. Obtained data have been processed by PRPD (phased resolved partial discharge) distribution function and K-means. And statistical and cluster distribution of partial discharge have been analysed and investigated.