FPN (fixed-pattern-noise) mainly comes from the device or pattern mismatches in pixel and color filter, pixel photodiode leakage in CMOS image sensor. In this paper, optical stack module related pixel FPN was investigated and the classification of pixel FPN contribution with the individual optical module process was presented. The methodology and procedure would be helpful in reducing the greater pixel FPN and distinguishing the complex FPN sources with respect to various noise factors.

Surface passivation of AlGaN/GaN heterojunction structure was examined through the thermal oxidation of evaporated Al. The Al-oxide passivation increased channel conductance of two dimensional electron gas (2DEG) on the AlGaN/GaN interface. The sheet resistance of 463 ohm/□ for 2DEG channel before Al2O3 passivation was decreased to 417 ohm/□ after passivation. The oxidation of Al induces tensile stress to the AlGaN/GaN structure and the stress seemed to enhance the sheet carrier density of the 2DEG channel. In addition, the Al2O3 films formed by thermal oxidation of Al suppressed thermal deterioration by the high temperature annealing.

In this study, in order to develop excellent lead free piezoelectric ceramics for piezoelectric actuators application, Li0.04(Na0.50K0.50)0.96[(Nb0.86Ta0.10Sb0.04)0.994Co0.015]O3+0.0025SrO + 0.15 wt%K2CO3 + x wt%Nb2O5 (x = 0 - 0.5 wt%) (abbreviated as LNKNTSCS-xN) ceramics were fabricated by a conventional sintering technique. the phase structure, microstructure and electrical properties were investigated with a emphasis on the influence of the Nb2O5 content. High electrical properties of d33= 234 pC/N, kp= 0.392, εr= 1,395, ρ= 4.70 g/cm3 were obtained from the specimen with x= 0.4 wt%, which suggests that the composition ceramics is a promising lead-free piezoelectric material.

The effect of oxygen pressure in the synthesis of ZnO nanostructures through thermal evaporation of Zn powder was investigated. The thermal evaporation process was carried out in oxygen ambient for 1 hr at 1,000℃ under different pressures. The oxygen pressure was changed in range of 0.5 ? 900 Torr. Any nanostructure was not formed on the specimens prepared at oxygen pressures lower than 10 Torr. When oxygen pressure was 100 Torr, ZnO nanowires were observed. With increasing the oxygen pressure to 500 Torr, the morphology of ZnO nanostructures changed from wire to tetrapod. For all the samples, room temperature photoluminescence spectra show a strong green emission peak at around 550 nm.

In this study we aims to examine the co-doping effects of 1/3 mol% Mn3O4+Co3O4 (1:1) on the reaction, microstructure, and electrical properties such as the bulk defects and grain boundary properties of ZnO-Bi2O3-Sb2O3 (ZBS; Sb/Bi=0.5, 1.0, and 2.0) varistors. The sintering and electrical properties of Mn,Co-doped ZBS, ZBS(MCo) varistors were controlled by Sb/Bi ratio. Pyrochlore (Zn2Bi3Sb3O14) was decomposed and promoted densification at lower temperature on heating in Sb/Bi=1.0 by Mn rather than Co. Pyrochlore on cooling was reproduced in all systems however, spinel (α- or β-polymorph) did not formed in Sb/Bi=0.5. More homogeneous microstructure was obtained in Sb/Bi≥1.0. In ZBS(MCo), the varistor characteristics were improved drastically (non-linear coefficient, α=30∼49), and seemed to form (0.17 eV) and (0.33 eV) as dominant defects. From impedance and modulus spectroscopy (IS & MS), the grain boundaries have divided into two types, i.e. the one is tentatively assign to ZnO/Bi2O3(Mn,Co)/ZnO (0.47 eV) and the other ZnO/ZnO (0.80∼0.89 eV) homojunctions.

In order to develop electrical insulation materials, epoxy-nanosilica-microsilica mixture composites (ENMC) was synthesized, and mechanical properties such as their tensile and flexural strength, and AC insulation breakdown strength were investigated. Properties of mechanical strength and AC insulation breakdown strength are analyzed as scale and shape parameter with respect to weibull plot. Their tensile and flexural strength, AC insulation breakdown strength were compared original epoxy or EMC to ENMC. The 4 phr nano-silica addition and the 65 wt% micron-silica mixture composite (ENMC) was found to have the highest tensile and flexural strength. In the tensile strength was improved 29%, and flexural strength was improved 60.9% higher than those of the original epoxy. In the insulation breakdown strength, ENMC_4 phr was improved 17% and ENMC_5 phr was improved 15.8% higher than those of the EMC.

In order to application for high voltage heavy electric equipments, epoxy/microsilica 60 wt%/nano layered silicate composites (EMNC_60) and epoxy/microsilica 65 wt%/nano layered silicate composites (EMNC_65) respectively was synthesized by our electric field dispersion method and the result was obtained completely dispersion state. Thermal properties such as glass transition temperature (Tg) and thermal expansion coefficient, and DMA characteristics were studied, and mechanical properties such as tensile and flexural tests were performed. AC electrical insulation strength was also tested. The study on thermal property, EMNC_65 was better than EMNC_60 and mechanical ,electrical properties much improved EMNC_60 compared with EMNC_65.

This study is explore the photoelectric conversion change of dye-sensitized solar cells with surface treatment of the conductive substrate. gases of FTO surface treatment were N2, and O2. Treatment conditions of surface were gas flux from 25 sccm to 50 sccm and RF power were from 25 W to 50 W. Treatment time and pressure were fixed 5 min and 100 mtoor. The best sheet resistance and surface roughness were obtained by O2 50 sccm and 50 W and that result were 7.643 Ω/㎠ and 17.113 nm, respectively. The best efficiency result was obtained by O2 50 sccm and 50 W and that result of Voc, Jsc, FF and efficiency were 7.03 V, 14.88 mA/㎠, 63.75% and 6.67%, respectively.

The address discharge characteristics of a open dielectric structure compared with the conventional panel structure are investigated by measuring the discharge firing voltage. The open dielectric structure could easily produce the discharge between the scan and the sustain electrodes by erasing the dielectric layer between two electrodes. Due to the changes in the discharge firing characteristics of the open dielectric structure between the two sustain electrodes, the conventional reset waveform including the address waveform needs to be modified. The modified driving waveform suitable for the open dielectric structure is proposed and examined in AC PDP.

We studied the emission characteristics of white phosphorescent organic light-emitting diodes (PHOLEDs), which were fabricated using a two-wavelength method. The best blue emitting OLED and red emitting OLED characteristics were obtained at a concentration of 12 vol.% FIrpic and 1 vol.% Bt2Ir(acac) in UGH3, respectively. And the optimum thickness of the total emitting layer was 25 nm. To optimize emission characteristics of white PHOLEDs, white PHOLEDs with red/blue/red, blue/red, red/blue and co-doping emitting layer structures were fabricated using a host-dopant system. In case of white PHOLEDs with co-doping structure, the best efficiency was obtained at a structure UGH3: 12 vol. % FIrpic: 1 vol.% Bt2Ir(acac) (25 nm). The maximum brightness, current efficiency, power efficiency, external quantum efficiency, and CIE (x, y) coordinate were 13,430 cd/㎡, 40.5 cd/A, 25.3 lm/W, 17 % and (0.49, 0.47) at 1,000 cd/㎡, respectively.

This research measured the dielectric properties of silicone rubber with various hardness in 100 Hz∼3 MHz, 30∼170℃ conditions. When the hardness increases from 65 degree to 75 degree, the dielectric loss increased within frequency range of 100 kHz～3 MHz and was a little change in dielectric loss within temperature range of 90℃～170℃. Thermogravimetric Analysis (TGA) showed the weight change rate increased a little while heated until 800℃. Scanning Electron Microscope (SEM) measurement showed that Aluminium Trihydroxide(AlOH3) which acts as a reinforcement agent reduced the size of the particles as the hardness increased.

Single crystalline Au nanowires were successfully synthesized in a tube-type furnace. The Au nanowires were grown by vapor phase synthesis technique using solid-liquid-solid (SLS) mechanism on substrates of corning glass and Si wafer. Prior to Au nanowire synthesis, Au thin film served as both catalyst and source for Au nanowire was prepared by sputtering process. Average length of the grown Au nanowires was approximately 1 μm on both the corning glass and Si wafer substrates, while the diameter and the density of which were dependent on the thickness of the Au thin film. To induce a super-saturated states for the Au particle catalyst and Au molecules during the Au nanowire synthesis, thickness of the Au catalyst thin film was fixed to 10 nm or 20 nm. Additionally, synthesis of the Au nanowires was carried out without introducing carrier gas in the tube furnace, and synthesis temperature was varied to investigate the temperature effect on the resulting Au nanowire characteristics.

The Sr0.7Bi2.3Nb2O9(SBNO) thin films were deposited on Si substrate by RF magnetron sputtering method at 300℃ of substrate temperature. And the SBNO thin films were annealed at 650～800℃ using RTA (rapid thermal annealing). The grain of SBNO thin films were increased with the increase of annealing temperature. The dielectric constant (100) of SBNO thin film was obtained by RTA above 750℃. The voltage dependence of dielectric loss showed a value within 0.03 in voltage ranges of -5～＋5 V. Also, the dielectric constant characteristics showed a stable value with the increase of frequency.

Newly developed Series hybrid low-floor articulated vehicle which can meet both road and railway running conditions. It has the rated driving speed of 80 km/h and three driving modes with hybrid(engine+battery) driving mode, engine driving mode, battery driving mode. The battery driving mode requires the several 10 km running without additional charging operation. The vehicle has been equipped with LPB (lithium polymer battery) pack for the series hybrid propulsion system. LPB pack consists of 168 cells (3.7 V in a cell, 80 Ah) in series, DC Circuit breaker, mechanical rack, BMS (battery management system). This paper has shown the design process of LPB pack and application to the vehicle. Driving results in the road was successful to be satisfied with the requirement of the series hybrid vehicle.

LED is divided to multichannel in order not to exceed a certain voltage in aspects of electric standard. However, it`s not possible to know in accordance with what channel SMPS controls the constant voltage and current. In order to solve this problem, it needs to detect the maximum LED String voltage which is applied to LED control circuit, and it is possible to minimize the voltage drop when a difference of LED string voltage occurs by each channel if LED is controlled by the maximum LED string voltage detected. In addition, it is also possible to maximize the efficiency of LED if change LED voltage by detecting the maximum voltage. Feasibility of this claim was verified through implementation of the circuit.