The etching characteristics of ZnO and etch selectivities of ZnO to SiO2 in SF6/Ar plasma were investigated using Inductively-coupled-plasma (ICP). The maximum etch rates of ZnO were 6.5 nm/min at SF6(50%)/Ar(50%), Source power (700 W), Bias power (250 W), Working pressure(8 mTorr). The etch rate of ZnO showed a non-monotonic behavior with increasing from 0% to 50% Ar fraction in SF6/ Ar plasma. The plasma diagnostic were characterized using Optical Emission Spectroscopy (OES) analysis measurements.

In this paper, reliability of the two sandwiched MIM capacitors of Al2O3-HfO2-Al2O3 (AHA) and SiO2-HfO2-SiO2 (SHS) with hafnium-based dielectrics was analyzed using two kinds of voltage stress; DC and AC voltage stresses. Two MIM capacitors have high capacitance density (8.1 fF/μm2 and 5.2 fF/μm2) over the entire frequency range and low leakage current density of ∼1 nA/cm2 at room temperature and 1 V. The charge trapping in the dielectric shows that the relative variation of capacitance (ΔC/C0) increases and the variation of voltage linearity (α/α0) gradually decreases with stress-time under two types of voltage stress. It is also shown that DC voltage stress induced greater variation of capacitance density and voltage linearity than AC voltage stress.

In this paper, flicker noise characteristic and channel hot carrier degradation of NMOSFETs with plasma nitrided oixde (PNO) and thermally nitrided oxide (TNO) are analyzed in depth. Compared with NMOSFET with TNO, flicker noise characteristic of NMOSFET with PNO is improved significantly because nitrogen density in PNO near the Si/SiO2 interface is less than that in TNO. However, device degradation of NMOSFET with PNO by channel hot carrier stress is greater than that with TNO although PMOSFET with PNO showed greater immunity to NBTI degradation than that with TNO in previous study. Therefore, concurrent investigation of the reliability as well as low frequency noise characteristics of NMOSFET and PMOSFET is required for the development of high performance analog MOSFET technology.

In this study, the characteristics and error ranges of the mechanical bonding strength were analyzed according to before and after thermal shock test for various chips of automotive application component using Sn-3.0Ag-0.5Cu solder. In the after thermal shock test, the mechanical bonding strengths tend to decrease, meanwhile decreasing rates of mechanical strengths were less then 12% at specimen`s bonding area below 3.5mm2, and were from 17 to 21% at specimen`s bonding area above 12 mm2. On the other hand, Specimen`s mean deviation rates were about 5% at specimen`s bonding area more than 12 mm2. Inversely, at specimen`s bonding area is less then 3.5 mm2, mean deviation rates were increased to about 8%. It means that the smaller device size is, the larger mean deviation rate. In addition, error ranges and deviation rates of the mechanical bonding strengths may differ slightly depending on their bonding area. Furthermore, process conditions as well as method of mechanical reliability evaluation should be established to reduce the error ranges of bonding strength.

We investigated the physical properties of stoichiometric and non-stoichiometric oxide doped complex perovskite, Ba(Zn1/3Ta2/3)O3 ceramics and their impacts on the microwave dielectric performances using various characterization techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and network analyzer. According to the measurement of lattice constant changes, anomalous lattice volume contraction of ZrO2 doped Ba(Zn1/3Ta2/3)O3 sample only showed the dielectric quality factor enhancements, which was due to the lattice volume contraction as well as the 1:2 B-site cation ordering. In addition, NiO doping was useful to the stabilization of temperature coefficient of resonance frequency.

In this study, we investigated the effects of Mn dopant (0.1∼3.0 at% Mn3O4 sintered at 100 0℃ for 1 h in air) on the bulk trap (i.e. defect) and grain boundary properties of ZnO, ZM(0.1∼3.0) using admittance spectroscopy (AS), and impedance-modulus spectroscopy (IS & MS). As a result, three kinds of defect were found below the conduction band edge of ZnO as 0.09∼0.14 eV (attractive coulombic center), 0.22∼25 eV (Zn¨(i)), and 0.32∼0.33 eV (V`o). The oxygen vacancy increased with Mn doping. In ZM, an electrically single grain boundary as double Schottky barrier was formed with 0.82∼1.0 eV of activation energies by IS & MS. We also find out that the barriers of grain boundary of Mn-doped ZnO (α-factor=0.13) were more stabilized and homogenized with temperature compared to pure ZnO.

In this study we aims to evaluate the effects of 1/3 mol% Co3O4 addition on the reaction, microstructure development, resultant electrical properties, and especially the bulk trap and grain boundary properties of ZnO-Bi2O3-Sb2O3 (Sb/Bi=2.0, 1.0, and 0.5) system (ZBS). The samples were prepared by conventional ceramic process, and characterized by XRD, density, SEM, I-V, impedance and modulus spectroscopy (IS & MS) measurement. In addition of Co3O4 in ZnO-Bi2O3-Sb2O3 (ZBSCo), the phase development, density, and microstructure were controlled by Sb/Bi ratio. Pyrochlore on cooling was reproduced in all systems. The more homogeneous microstructure was obtained in ZBSCo (Sb/Bi=1.0) system. In ZBSCo, the varistor characteristics were improved drastically (non-linear coefficient α=23∼50) compared to ZBS. Doping of Co3O4 to ZBS seemed to form V*o (0.33 eV) as dominant defect. From IS & MS, especially the grain boundary of Sb/Bi=0.5 system is composed of electrically single barrier (0.93 eV) and somewhat sensitive to ambient oxygen with temperature.

Non-wovens polyester rayon samples were manufactured, and the electrification properties of electrostatics were measured for three different samples (15 g/m2, 25 g/m2, and 40 g/m2) with the environmental settings of temperature (20~40℃) and humidity (40~90%). The conclusions are as follows. Heavy sample generated more static electricity when the temperature was constant. The static electricity decreased slowly when the humidity is less than 70%, while it sharply decreased over 70% humidity condition. For non-woven polyester rayon, static charge decreased as temperature and humidity increased. As the weight increased, less time were taken for the electrification voltage to drop to the half.

In this study, Ge8Se(2+x)Te(6-x) thin film amorphous-to-crystalline phase-change rate was evaluated in using a nano-pulse scanner. The focused laser beam with a diameter <10 μm was illuminated in the power (P) and pulse duration (t) ranges of 1-31 mW and 10-460 ns, respectively, with subsequent detection of the responsive signals reflected from the film surface. We also evaluated the material characteristics, such as optical absorption and energy gap, crystalline phases, and sheet resistance of as-deposited and annealed films. The result of experiments showed that the thermal stability of the Ge-Se-Te film is largely improved by adding Se.

We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different device structure as a bottom and top contact FET. Also, we used a SiO2 as a gate insulator and analyzed using a current-voltage (I-V) characteristics of the bottom and top contact CuPc FET device. In order to discuss the channel formation, we were observed the capacitance-gate voltage(C-V) characteristics of the bottom and top contact CuPc FET device.

The optical properties of ZnO thin film, being treated by O-plasma, have been studied using Photoluminescence(PL) spectroscopy with the change of temperature from 10 K to 290 K. Two characteristic peaks were identified at 10 K:3.357 eV(DoX) and 3.324 eV(TES). The peak of DoX is believed to be due to neutral donor bound excitons where the donor is in the ground state. However, the TES(Two Electron Satellite) peak indicates the excited state of the donor(excitation energy was ~30 meV). The donor binding energy was estimated to be 44 meV, which indicates the possible presence of the neutral donor bound excitons at RT. The thermal effect including thermal broadening was identified from temperature evolution of the spectrum. Both the peak intensity and the peak energy have decreased as the temperature increases. As the temperature approaches to RT, the two peak merges into one broad peak, which is considered a combination of multiple peaks having different physical origins.

A bushing is very important because it must supply the high voltage to the power equipment. Generally, the surface of bushing is contaminated with rain, dust, salt and others. A bushing with contaminations at air are serious problem in insulation. Therefore, it is important to understand the inspection and diagnoses of the safety. The ultra-violet rays(UV) camera has attracted interest from the view point of easy judgement. In this paper, we will report on the corona discharge characteristics on bushing model with contaminations. Also, UV images of discharge in air are analyzed using prototype UV camera of Korea. These results are studied at both AC and DC voltage under a non-uniform field.

The light extraction efficiency of top-emitting organic light-emitting diode (OLED) was improved by insertion of corrugation patterns between indium tin oxide and organic layers. The corrugation patterns was fabricated by nanosphere lithography, which could form a self-assembled particle monolayer over a large area. The electrical and optical properties for the OLED devices fabricated by vacuum evaporation, were investigated. We have demonstrated the enhancement of the power efficiency of corrugated OLED. As a result, the power efficiency of the corrugated OLED was found to be more than 42%.

The use of plated front contact for metallization of silicon solar cell may alternative technologies as a screen printed and silver paste contact. This technologies should allow the formation of contact with low contact resistivity a high line conductivity and also reduction of shading losses. A selective emitter structure with highly dopes regions underneath the metal contacts, is widely known to be one of the most promising high-efficiency solution in solar cell processing. When fabricated Ni/Cu plating metallization cell with a selective emitter structure, it has been shown that efficiencies of up to 18% have been achieved using this technology.

Nowadays, with improvement of economical income and life qualities, life pattern changes have been brought such as increasing of avocational activities. Consequently, following those life trends, utilization of car is getting increased. Thus, the perceptions of car have been changed from the only means of transport in the past to a 2nd residental space. that is why the car`s endo environmental factors are getting so important. Air conditioner regulating air ventilization in vehicle`s indoor automatically sets the right temperature based on the differences of indoor and outdoor`s temperature with development of advanced functions to provide better environmental qualities in vehicle. However, even those advanced techniques for functional development are got so diverse though, the essential technique for preventing the growth of bateria and mold inside of the air conditioner are not even severals. Especially, evaporator one of the vehicle air conditioning equipments generates cooled air by vaporizing refrigerant in liquid state with the water as the adduct for this reactions. It has structural difficulties for water vaporation then cause the growth of germs. That`s why this reseach was focused on the way of eliminating germs in the vehicle air conditioner efficiently. Direct air sterilizer by using UVC(Ultraviolet C) is manufactured and that performances are evaluated.