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Both an unreinforced Al₂O₃/Al matrix and a α-Al₂O₃ particulate reinforced composite have been produced by the oxidation of an Al surface doped with NaOH in the absence of any other dopant. Fabrication of the matrix was initiated by the formation of NaAlO₂, which provides a favorable surface structure for the matrix formation by breaking the protective Al₂O₃ layer on Al. During the matrix growth, the external surface of the growth front was covered with a very thin sodium-rich oxide. A cyclic formation process of the sodium-rich oxide on the growth surface was proposed for the sodium-induced directed metal oxidation process. This process involves dissolution of the sodium-rich oxide, motion of Na to the growth front, and re-formation of the oxide on the surface. Near-net-shape composites were fabricated by infiltrating an Al₂O₃/Al matrix into a α-Al₂O₃ particulate preform, without growth barrier materials. The infiltration distance increased almost linearly in the NaOH-doped preform.

The bi-modal breakdown processes can well explain the lifetime model in grooved gate oxide with rounded local structure. We have clarified for the first time that the gate oxide reliability is strongly dependant on the tunneling characteristics in the rounded channel of the center and the N+ junction edge corners

Carbon–carbon composites are often used in high-temperature applications due to their high specific modulus, high specific strength, excellent heat resistance, high thermal shock resistance and chemical inertness. In this paper, the strength of carbon/carbon brake disks for automotive applications were tested and evaluated. The laminate material properties of carbon/carbon composites were evaluated via tension, compression and shear tests. The strengths of mechanically fastened composite joints for brake disks were tested and their failure criterion was established based on the maximum stress theory. Additionally, torsion tests of carbon/carbon brake disks were performed and the results were compared with those from a finite element analysis.

Polyaluminocarbosilane was synthesized by direct reaction of polydimethylsilane with aluminum(Ⅲ)-acetylacetonate in the presence of zeolite catalyst. A fraction of higher molecular weight polycarbosilane was formed due to the binding of aluminium acetylacetonate radicals with the polycarbosilane backbone. Small amount of Si-O-Si bond was observed in the as-prepared polyaluminocarbosilane as the result. Polyaluminocarbosilane fiber was obtained through a melt spinning and was pyrolyzed and sintered into SiC fiber from 1200~2000℃ under a controlled atmosphere. The nucleation and growth of β-SiC grains between 1400 - 1600℃ are accompanied with nano pores formation and residual carbon generation. Above 1800℃, SiC fiber could be sintered to give a fully crystallized β-SiC with some α-SiC.

Polycarbosilane is the most typical polymeric precursor for SiC ceramic. In this study, liquid type polycarbosilane was synthesized from polydimethylsilane in the presence of solid acid catalyst at 350oC. The molecular weights of the polycarbosilane were ranged between 350 and 530. Synthesized polycarbosilane was characterized with 29Si Solid NMR, FT-IR and GPC analysis. The synthesized polycarbosilane can be used as a good organometallic precursor for SiC coating via chemical vapor deposition or spin coating.

Four kinds of raw C/C composites with a density between 1.25~1.66g/㎤ were used in order to investigate the effect of the initial porosity of C/C composites on mechanical properties of liquid silicon infiltrated C/SiC composites. The microstructure observation, image analysis and flexural strength test of the composites were performed. The density and microstructural changes with the variation of the initial porosity was discussed in the terms of the infiltration behavior of liquid silicon and the reaction between liquid silicon and matrix carbon.

Graphite is widely used in electronic industry due to its excellent electrical and thermal properties. However, graphite starts to oxidize around 350°C which seriously degrades its properties. SiC coating can be applied to graphite to improve its high temperature oxidation resistance. In this research, SiC coating on graphite was made via preceramic polymer using a polymethylphenylsilane. 20% of polymethylphenylsilane in hexane solution was coated onto graphite by dip coating method. After coating, thermal oxidation was carried out at 200°C for crosslink of the preceramic polymer and the sample were pyrolysized at 1200°C under nitrogen to convert the preceramic polymer to SiC film. The phase formation, stiochiometry and microstructure of the SiC coating after pyrolysis were investigated using low angle XRD and FESEM etc. Oxidation resistance up to 600°C was evaluated.

The paper presents layout dependency of PMOS I off degradation during off-state stress, which is induced by inverter leakage currents (I off ) have been increased by electron trapping in PMOSFET. Extensive test result represents time dependence of PMOS hump is based on the STI edge trap. To conclude, we can expect that hot temperature bake evaluation causing partial recovery of I off leakage is the reason for that trap location is a nitride liner of STI edge rather than edge gate oxide.

An exact lifetime extrapolation models of ZrO2-Al2O3-ZrO2 (ZAZ) stack capacitor with metal-insulator-metal (MIM) structure was studied in this paper. From the extensive long-term test result (~ 7.5 months) it was found that the power-law model is suitable as a exact lifetime extrapolation model for ZAZ dielectric reliability.

We fabricated electromagnetic micro x-y stage for application to probe based mass data storage (PDS) devices. The stage consists of Si body containing planar copper coils, glass substrate bonded to the body, and 8 permanent magnets. The dimensions of springs and copper coils were determined so that a current of 100 mA would provide 50 μm motion in x and y. For application to PDS device, electromagnetic stage should have a flat top surface and coils of low resistance. So conducting planar copper coils have been electroplated within silicon trench of high aspect ratio (5 μm in width and 30 μm in depth). As insulating layer, polyimide was used. Silicon flexures with the height of 250 μm were fabricated by using ICP-RIE (Inductively Coupled Plasma Reactive Ion Etching). The characteristics of the fabricated electromagnetic stage were measured by LDV (Laser Doppler Vibrometer) and DSA (Dynamic Signal Analyzer). DC gain was 0.16 μm/mA and the maximum displacement was 42 μm at a current of 180 mA. The natural frequency was 325 Hz.

— A pixel structure for shutter-glasses-type stereoscopic 3-D active-matrix organic light-emitting-diode (AMOLED) displays is proposed. The proposed pixel programs data to the pixel during the light-emission time of an OLED. Because the emission time of the proposed pixel is extended, it is expected that the proposed pixel not only decreases the peak current of the OLED during the emission period but also reduces flicker. Moreover, the aperture ratio of the proposed pixel is 58.69% for a 50-in. full-high-definition (FHD) condition by minimizing the number of thin-film transistors (TFTs), capacitors, and control signal lines as seven TFTs, two capacitors, two power lines, and four control lines per unit pixel. Simulation results show that the error in the emission current of the proposed pixel is from −0.82% to +0.90% when the threshold-voltage variation of the driving TFT is ±1.00 V, and the maximum variation of the emission current is −1.35% when a voltage drop in the power line is −0.50 V on a full-white-image display.

The world's largest (15-inch) XGA active matrix liquid crystal display (AMLCD) panel made with IGZO TFTs (W/L=29.5/4 μm) was fabricated and evaluated with the field effective mobility of 4.2±0.4 cm2/V-s, Vth of −1.3±1.4V and sub-threshold swing (SS) of 0.96±0.10 V/dec. for a manufacturing-oriented process, the main factors affecting threshold voltage (Vth) of the IGZO thin film transistors (TFT) are investigated. On the glass surface, thicker regions of IGZO film have a negative threshold voltage shift. A dry etching process of molybdenum source and drain (S/D) causes negative shift of the average threshold voltage compared to wet etching in the bottom gate back channel etched TFTs. However, optimization of SiOx passivation and subsequent annealing shift average Vth positively and reduce Vth variation.