This paper was analyzed electrical characteristics of super junction IGBT with super junction field rings. As a result of super junction IGBT with super junction field rings, we obtained 3,300 V breakdown voltage and good thermal characteristics. we obtained shrinked chip size because field ring was decreased than field ring for conventional IGBT, too. And we fabricated super junction IGBT with super junction field rings. As a result of measuring fabricated chip, we obtained 3,300 V breakdown voltage. The fabricated devices were replaced thyristos using high voltage conversion, sufficiently.

This paper was proposed 900 V Power MOSFET with ESD protection circuits using zener diodes. And we were carried out and analyzed its electrical characteristics. As a result of designing 900 V power MOSFET, we obtained 1,000 V breakdown voltage, 3.49 V threshold voltage and 0.249 Ω·cm2. And we designed ESD circuits using 2 series zener diode and 4 series zener diodes. After analyzing electrical characteristics, we obtained 26 V forward voltage drop and 47 V breakdown voltage. Therefore, This devices can enoughly use power module, SMPS and Automotive.

Nano-size BaTiO3 powder was synthesized by relatively simple hydrothermal reaction method. Finely dispersed Ti hydroxide precursor was first precipitated using Ti(SO4)2 and NaOH solution by applying ultrasonic power and washed thoroughly to remove SO4 2- and Na+ ion. Then hydrothermal reaction was done at 160℃ for 6 hrs using solution prepared by washed Ti hydroxide precursor slurry and Ba(OH)2ㆍ8H2O with Ti:Ba mole ratio of 1:1. 200 ~ 500 nm size and uniform size distributed BaTiO3 powder was synthesized by relatively low temperature and simple process.

The haptic actuator needs to downsize in the mobile devices continuatively. In this work, the hinge lever mechanism was used in order to prevent lowering the vibration performances of the downsized actuator. The vibration performances of actuator with and without hinge-lever mechanism were simulated by the finite element method analysis. It is concluded that the hinge-lever mechanism may be a proper measure to prevent lowering the vibration performances in the downsized piezoelectric actuator.

In this study, we developed a lead-free P_{2}`O_{5}`-V_{2}O_{5}-ZnO glass frit for sealing OLED using laser irradiation. The frit satisfied the characteristics required for laser sealing such as low glass transition temperature, low coefficient of thermal expansion (CTE), high water-resistance, and high absorption at the wavelength of the laser beam. Ceramic fillers were added to the glass frit in order to further reduce and match its CTE with that of the commercial glass substrate. The addition of Zirconium Tungsten Phosphate (ZWP) to the frit yielded the most desirable results, reducing the CTE to 45.4×10^{-7}/℃, which is very close to that of the glass substrate (44.0×10^{-7}/℃). Successful formation of a solid sealing layer was observed by optical and scanning electron microscopy.

In this paper, in order to develop the composition ceramics with the outstanding piezoelectric properties, (Mg_{1/2} W _{1/2} )_{0.03} (OWNS_{1/3} Nb_{2/3})_{0.09} (Zr_{0.5} Ti_{0.5})_{0.88} O_{3} ceramics substituted with BiFeO_{3} were prepared by the conventional solid-state reaction method. The addition of small amount of Li2CO_{3} and CaCO_{3} as sintering aids decreased the sintering temperature of the ceramics. The effects of BiFeO3 substitution on their piezoelectric and dielectric properties were investigated. when 0.015 mol BiFeO_{3} was substituted, the optimal physical properties of d33=590 pC/N, Ec=8.78 kV/mm were obtained.

We studied optical and electrical properties of two-wavelength white tandem organic light-emitting diodes using red and blue materials. White fluorescent OLEDs were fabricated using Alq3 : Rubrene (3 vol.% 5 nm) / SH-1 : BD-2 (3 vol.% 25 nm) as emitting layer (EML). White single fluorescent OLED showed maximum current efficiency of 9.7 cd/A, and tandem fluorescent OLED showed 18.2 cd/A. Commission Internationale de l``Eclairage (CIE) coordinates of single and tandem fluorescent OLEDs was (0.385, 0.435), (0.442, 0.473) at 1,000 cd/㎡, respectively. White hybrid OLEDs were fabricated using SH-1 : BD-2 (3 vol.% 10 nm) / CBP : Ir(mphmq)2(acac) (2 vol.% 20 nm) as EML. White single hybrid OLED showed maximum current efficiency of 7.8 cd/A, and tandem hybrid OLED showed 26.4 cd/A. Maximum current efficiency of tandem hybrid OLED was more twice as high as single OLED. CIE coordinates of single hybrid OLED was (0.315, 0.333), and tandem hybrid OLED was (0.448, 0.363) at 1,000 cd/㎡. CIE coordinates in white tandem OLEDs compared to those for single OLEDs observed red shift. This work reveals that stacked white OLED showed current efficiency improvement and red shifted emission than single OLED.

In this study, the electrification voltage of electrostatics for silicone rubber sample(4 cm × 4 cm × 0.103 cm) following immersion with contaminants of 2 ml, 5 ml, 10 ml for six hours has been measured in through the applied voltage of 10 kV DC at temperature of 80℃∼110℃, humidity of 50%∼90%. The results of this study are as follows. In case the contaminants is constant, it found that the electrification voltage of electrostatic decreased with increasing temperature and humidity to 35℃, 90%. In case of 2 ml of contaminants concentration, it found that the electrification voltage of electrostatic decreased with increasing temperature and humidity to 35℃, 50%. In case of the sample at temperature of 15℃ and humidity of 50%, it found that the electrification voltage of electrostatic decreased with increasing contaminants to 10 ml.

Ni ink for electrohydrodynamic (EHD) continuous jet printing has been developed by using Ni nanoparticles mixed with conhesiveness provider. EHD continuous jet printing was used in order to realize 20 μm pattern width. Ink stability was investigated by using Turbi-scan which monitors agglomeration and precipitation of nanoparticles in the ink for three days. The Turbi-scan results showed that the formulated Ni ink had been stable for 3 days without any indication of precipitation across the entire ink. Antireflection coating (ARC) layer in crystalline solar cell wafers was removed by laser ablation technique leading to the formation of 84 grooves where the Ni ink was printed by EHD continuous jet printing. The printability and microstructure of EHD-jet-printed Ni lines were investigated by using optical and electron microscopes. 84 Ni lines with the width less than 20 μm were successfully printed by one-time printing without any misalignment and fill the laser-ablated ARC grooves.

The Sr0.7Bi2.3Nb2O9(SBN) thin films are deposited on Pt electrode(Pt/Ti/SiO2/Si) using RF sputtering method at various deposition temperature. The deposition temperature of optimum was 300℃. SBN thin films were annealed at 500∼700℃ using furnace and RTA, respectively. The surface roughness showed about 2.42 nm in annealing temperature(600℃) of furnace. The capacitance density of SBN thin films were increased with the increase of annealing temperature. The maximum capacitance density of 0.7 ㎌/㎠was obtained by annealing temperature(700℃). The frequency dependence of dielectric loss showed about 0.03 in frequency ranges of 1∼1,000 kHz.

This paper presents a ZigBee wireless communication system for remote diagnosis in overhead distribution power lines. The system is divided in three parts in the functional aspect - a host computer module, a remote controller module and a diagnostic system module. The host computer module designed as USB interface transmits control signals and receive data measured by sensor. The remote controller module operates the diagnostic system. Diagnostic system module communicates with internal main controller and host computer USB. Multiple communication channel is adopted for simultaneous operations of several diagnostic system. Dedicated protocol for each module is developed. The system is designed with a focus on low cost and small size suitable for lightweight and small diagnostic system.

To provide the clear images from the direct light on electrical board and display devices, anti glare treatment of display cover glass is needed. In this study, the effects of surface treatment temperature, concentration, and etching solution coating thickness of the gel phase on optical elements control such as gloss, haze of reflected light and transmittance, were investigated. Cover glasses were treated at different coating thickness and additive concentration. The optical properties were examined using spectrophotometer, gloss and haze meter. The surface morphology and roughness were measured by the optical microscope and Ra measuring instrument. The etching rate and surface morphologies were dramatically affected by the concentration of acid additive in the viscous gel because of re-crystallization of components in the etching solution, hydrogel formation and coagulant after coating on glass substrate. In our experimental range, cover glass which is surface-treated with various optical properties as well as the morphology uniformity was obtained; in particular, optical properties could be controlled by etching solution coating thickness of the gel phase and the concentration of additive. The gloss was depended on the surface roughness and it showed the linear relationship between optical transmittance and haze of reflected light, respectively.