It is summarized that potential causes of performance degradations and failure mechanisms ofcrystalline silicon photovoltaic (PV) modules installed in Middle East area. In addition, we also reviewedcurrent PV module qualification test (IEC 61215) and the methods for detection of wear-out fault. Thefailure of PV modules in the extreme environmental conditions such as deserts is mainly due to hightemperature, humidity, and dust storms. In particular, cementation phenomenon caused by combination ofsand and moisture leads to rapid degradation in the performance of PV modules. In order to evaluate andguarantee the long term reliability of PV modules, specific qualification tests such as sand dust test, saltmist test and potential induce degradation test considering operating environment of PV module should becarried out.

Bottom-gate tin oxide (SnO2) thin film transistors (TFTs) were fabricated on N+ Si wafersused as gate electrodes. 60-nm-thick SnO2 thin films acting as active layers were sputtered onSiO2/Al2O3 films. The SiO2/Al2O3 films deposited on the Si wafers were employed for gate dielectrics. Inorder to increase the resistivity of the SnO2 thin films, oxygen mixed with argon was introduced into thechamber during the sputtering. The mobility of SnO2 TFTs was measured as a function of the flow ratioof oxygen to argon (O2/Ar). The mobility variation with O2/Ar was analyzed through studies oncrystallinity, oxygen binding state, optical properties. X-ray diffraction (XRD) and XPS (X-rayphotoelectron spectroscopy) were carried out to observe the crystallinity and oxygen binding state ofSnO2 films. The mobility decreased with increasing O2/Ar. It was found that the decrease of the mobilityis mainly due to the decrease in the polarizability of SnO2 films.

In this paper, the effect of underpass structure on quality factor and breakdown voltage ofoctagonal inductors which were fabricated with 90 nm complementary metal-oxide-semiconductor (CMOS)technology for radio frequency integrated circuit (RFIC) was studied. It was found that quality factor andbreakdown voltage of inductors with more than one metal layer for underpass showed improvedproperties compared to those with one metal layer. However, little change of quality factor andbreakdown voltage was observed between the inductors with two and more than two metal layers forunderpass. Therefore, underpasses with two metal layers are promising for RFIC designs of the octagonalinductors in 90 nm CMOS technology.

MnO2-doped 0.985[Li0.04(Na0.545K0.46)0.96(Nb0.81Ta0.15Sb0.04)]O3+0.015KNbO3(0.985LNKNTS+0.015KNbO3)lead-free ceramics were fabricated by conventional solid state method to develop excellent dielectric andpiezoelectric properties. The result of X-ray diffraction patterns obviously indicated that all of thespecimen has pure perovskite structure without secondary phase. In addition, orthorhombic phase andcoexistance region of orthorhombic-tetragonal phase (MPB) were observed with amount of MnO2. Theoptimal values of ρ=4.70 g/cm3, d33=238 pC/N, kP=0.46, Qm=121, εr=849, and TC=225℃ were obtained at0.01 mol% MnO2 doped 0.985LNKNTS+0.015KNbO3 ceramics sintered at 990℃ for 5 h, respectively. Hence, it was indicated that the suitable amount of MnO2 could improve the electrical properties of0.985[Li0.04(Na0.545K0.46)0.96](Nb0.81Ta0.15Sb0.04)]O3+0.015KNbO3 ceramics.

We investigated dielectric relaxation properties of 0.95(Na0.5K0.5)NbO3-0.05BaTiO3 ceramics byaddition (0∼0.3 wt%) of (Ba,Ca)SiO3 glass frit. All composition of 0.95(Na0.5K0.5)NbO3-0.05BaTiO3 added(Ba,Ca)SiO3 glass frit showed the same crystallographic properties, coexistence of orthorhombic andtetragonal phase. By increasing addition of (Ba,Ca)SiO3 glass frit, the Curie temperatures of0.95(Na0.5K0.5)NbO3-0.05BaTiO3 ceramics were decreased, whereas maximum dielectric constants of0.95(Na0.5K0.5)NbO3-0.05BaTiO3 ceramics were dramatically increased. Especially the deviations of Curietemperature 0.95(Na0.5K0.5)NbO3-0.05BaTiO3 ceramics were increased by increasing amount of(Ba,Ca)SiO3 glass frit, and it indicated that 0.95(Na0.5K0.5)NbO3-0.05BaTiO3 ceramics added (Ba,Ca)SiO3glass frit have relaxor characteristics.

We investigated the effect of excess CuO on the sintering behavior, ferroelectric, andpiezoelectric properties of lead-free Bi0.5(Na0.82K0.18)0.5TiO3 (BNKT) ceramics. The addition of excess CuOwas found to greatly contribute to the densification and grain growth, however, excess CuO over 3 mol%was precipitated at grain boundaries after sintering. BNKT with 1∼2 mol% CuO in excess sintered at975℃ showed piezoelectric properties comparable to those of unmodified BNKT sintered at 1,175℃. These results seem meaningful for its application to low cost multilayer actuators (MLAs) becauselow firing ceramics make it possible to apply less expensive base metals to the inner electrode ofMLAs.

We have investigated the effects of spacer layer inserted between blue and red doped emissionlayers on the emission and efficiency characteristics of phosphorescent OLEDs. N,N``-di-carbazolyl-3,5-benzene(mCP) was used as a host layer. Iridium(III)bis[(4,6-di-fluorophenyl)- pyridinato-N,C2``]picolinate (FIrpic) andtris(1-phenyl-isoquinolinato-C2,N)iridium(III) [Ir(piq)3] were used as blue and red dopants, respectively. Theemission layer structure was mCP (1-x) nm/mCP:Ir(piq)3 (5 nm, 10%)/mCP (x nm)/mCP:FIrpic (5 nm, 10%). The thickness of mCP spacer layer was varied from 0 to 15 nm. The emission from Ir(piq)3 and theefficiency of the device were dominated by energy transfer from mCP host and FIrpic molecules, and bydiffusion of mCP host triplet excitons.

The relay used is gradually increased. Because it is possible to easily control the high voltageand current. Bounce phenomenon is generated in contact during operation relay. As the result, arc isgenerated at the contact, thereby shortening the contact lifetime. In this study, we analyzed the bouncingphenomenon due to deterioration. It can be seen from the experimental results, and it is minimized atabout 100,000 times. Bouncing phenomenon to increase again after the minimization. Consequently, thebouncing related to contact weight and shape of contact surface.

A thin metal-embedding Schottky device was fabricated for an efficient photoelectric device. Semitransparent thick of 10 nm metal layers were deposited by sputtering of Ag and Ni on a Sisubstrate. The (111) N-type Si wafers with one-side polished, 450∼500 ㎛ and resistivity 1∼20 Ω·㎝were used. High rectifying ratio about 100 from Ni-Schottky device was achieved. This design wouldprovide an effective scheme for high-performing photoelectric devices.

We fabricated the electrolyte-dielectric-metal (EDM) sensor on the base of AAO (anodicaluminum oxide) template with variation of the anodizing temperature. When a surface is immersed orcreated in an aqueous solution, a discontinuity is formed at the interface where such physicochemicalvariables as electrical potential and electrolyte concentration change significantly from the aqueous phaseto another phase. Because of the different chemical potentials between the two phases, charge separationoften occurs at the interfacial region [1]. This interfacial region, togeter with the charged surface, isusually known as the electrical double layer (EDL) [2]. The structural and electrochemical properties ofAAO sensor were investigated for applications in capacitive pH sensors. To change the thickness of theAAO template, the anodizing temperature was varied from 5℃ to 20℃, the thickness of the AAOtemplate invreased from 300 nm to 477 nm. The pH sensitivity of sensors with the anodizing temperatureof 20℃ showed the highest value of 56.4 mV/pH in the pH range of 3 to 11. The EDM sensor with theanodizing temperature of 20℃ exhibited the best long-term stability of 0.037 mV/h.

Thermal batteries are used for military power sources that require robustness and long storagelife such as missiles and torpedoes. FeS2 powder is currently used for cathode materials because of itshigh specific energy density, environmental non-toxicity and low cost. However, large particle size ofconventional FeS2 has been deterred its possible application for higher power thermal batteries. In order toimprove the power density, high energy ball milling of FeS2 has been introduced to crush the micron-sizedFeS2. Discharge characteristics of the single cells fabricated with nano-materials and conventional FeS2powder were evaluated.

Five factors are identified, which affect the performance of optical filter: 1) type of opticalglass, 2) existence of Fe, 3) photo pic coating type, 4) coating form, and 5) coating thickness. If weconsider all the levels of five factors, there are 360 possible candidates. We determined five evaluationcriteria, which can be used to evaluate possible candidates. For the performance measures we selectedwhite-state avearge voltage, black-state average voltage, and black-state error rate. And we addedeconomic criterion and quality and maintenance criterion. Through the two-step statistical analysis ofwhite-state avearge voltage, black-state average voltage, and black-state error rates, we selected finalfour candidates. Based on the five criteria we finally determined optimal optical filter using AHP.