The top emission organic light-emitting diodes (TEOLEDs) with multilayer electrodes were studied. Firstly a high reflectivity metal, Al, followed by a high work function metal, such as Pt, Ni or Au, was used as bilyaer anode. It was found that the Al/Au bilayer anode can give rise to a very good luminescent performance if the Al thickness in the bilayer was adjusted to 70 nm. The Al/Au bilayer anode has high reflectivity and good adhesive contact with the hole injection layer. Next the cathode in TEOLEDs composed of multiple layers, LiF/Al/Ag, were studied. The optimum thicknesses in each layer as 0.4/4/15 nm were used to achieve high transparency and good conductivity. The effects of thicknesses of each organic layer were also studied. When the optimum thicknesses of m-MTDATA/NPB/Alq3 were adjusted to 20/40/60 nm, the highest brightness and best luminance efficiency of 8041 cd/m2 and 3 cd/A, respectively, were obtained. The white TEOLED was also studied in this thesis. The ADS082BE was blue host-emitting material and DCJT was orange guest-emitting material. The doped concentration and location were adjusted to control the blue to orange luminance intensity ratio. A white emission with CIE coordinate (0.30, 0.34) was obtained. The highest luminance of 3739 cd/m2 @13.5 Vand best luminance efficiency of 3 cd/A@10V were obtained in the white TEOLED which used multilayer anode and cathode structures. Finally TEOLEDs were also fabricated on the Si wafer and flexible substrate. The brightness and luminance efficiency were (3894 cd/m2;3.8 cd/A on Si wafer),(575 cd/m2, 1.46 cd/A on PES substrate).

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In this thesis we proposed two new pixel circuits for organic light emission display. The first one is 5T1C circuit with two control signals. It can compensate threshold voltage variation and the drop of the power supply voltage that result in OLED current non-uniformity. We have demonstrates that the pixel circuit has high immunity to the threshold voltage variation. In addition, the circuit uses low supply voltage compared with the conventional 5T1C pixel circuit, so it is a low power driver circuit. The second one employs the voltage feedback method and uses the gain value of design circuit for compensating the threshold voltage shift of the driving TFT.To the aim is to reach that to the flow through current of the driving TFT have no relationship with the threshold voltage of TFT. Thus, the OLED can emission light with retaining uniformity light in each time. Because the proposed circuit configuration has low supply voltage and low select pulse voltage, the spike wave phenomenon can be improved and eliminated while the circuit switchs on and off. Due to the circuit supply voltage is decreased, it power consumption reduce significantly and the capacitor charging time is less than 70 £gs. Thus, in this thesis, the two proposed pixel circuits are both of low voltage and low power. The two pixel circuits designed have been fabricated by TSMC 0.35£gm 2P4M CMOS technology with 3.3v power supply. The 5TIC chip area is 1031.8 ¡Ñ 1083.7£gm2 and the measured result shows that when the select pulse is 0~10V, the input voltage is 10V, the select pulse2 is 0~8V and the Vdata¡@voltage range is 0~5V, the OLED current is correspond to 0~20.6£gA and the maximum power consumption is 17£gw. The chip area of the voltage feedback circuit is 1083.38 ¡Ñ 1149.8£gm2 and the measured result shows that when the select pulse is 0~10V, the input voltage is 10V and the feedback resistor is 50£[, the power consumption is 72£gw and the charging time is 51.7£gs.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 156-162). Available also in a digital version from Dissertation Abstracts.

Thesis (M.S.)--Naval Postgraduate School, 2002. / Thesis advisor(s): Gamani Karunasiri, James Luscombe. Includes bibliographical references (p. 45-46). Also available online.

Thesis (M.S.)--Mississippi State University. Department of Agricultural and Biological Engineering. / Title from title screen. Includes bibliographical references.

Thesis (M.S. in Applied Physics)--Naval Postgraduate School, March 2004. / Thesis advisor(s): Bruce C. Denardo. Includes bibliographical references (p. 59-60). Also available online.

Using the vapor-liquid-solid (VLS) growth method, silicon nanowires and germanium nanowires are grown. We find the high growth rate is responsible for the silicon nanowires with less growth defects when they are grown by use of silicon tetrachloride as a precursor and hydrogen as a carrier gas. Based on this funding, large area, high aspect ratio, h111i oriented silicon nanowires are successfully grown on Si (111) and Si (100). Novel growth mechanisms of VLS growth method were discovered in SiOx nanoflowers and silicon nanocones. In SiOx nanoflowers grown at the tip of silicon nanowires, it is found that they are produced via the enhanced oxidation of silicon at the gold-silicon interface. Furthermore, the analysis of the flower pattern reveals that it is the observation of the dense branching morphology on nanoscale and on spherical geometry. For the silicon nanocones, they are grown by the in situ etching of the catalysts of Ga/Al by HCl during the growth. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) reveal that the nanocones are composed of amorphous silicon oxides and crystalline Si. Based on the similar chemistry of hydrogen reduction of SiCl₄ for the growth of silicon nanowires, single crystalline germanium nanowires are grown by use of GeCl4 as a precursor and H₂ as a carrier gas. As one of important application of one dimensional nanostructures, the field emission properties of 1-D nanostructures are explored. The field emission properties of a single graphite nanocone are measured in SEM. The inter-electrode separation is controlled using scanning tunneling microscopy (STM) approach method, allowing the precise and ne determination of the separation. Its Fowler-Nordheim plot shows it emits currents in accordance with the Fowler-Nordheim field emission. Its onset voltage, field enhancement factor show that its basic field emission parameters are comparable to those of a single carbon nanotube. It is observed that single nanocone is damaged after emitting a current of about 100 nA, which seems to be due to its hollow interior structure. / text

In recent years, much attention has been focused on the application of alternutive gaseoas fuels, particularly natural gas (lVG), to diesel engines. This is due to the promisiog results obtained from the resesrch on NG as an internal combustion engine fuel throughout the world which hus shown that there is potential fo, minimizing air pollution and noise by replacing diesel fuel in existing engines by lfc fuel. For partial substitution of diesel fuel with IfG fuel in a diesel engine, a mixed combustion process called daal-fuelling approach has been adopted. Dual fuelling is the method whereby an alternative gaseous fuel such as IYG is induced into the cylinder as a primary fuel, with oir, and is subsequently ignited with a pilot injection of diesel fael. Extensive tests on emissions, performonce and dilferent umounts of NG substitution in a direct injection (DI) diesel engine have been carried out fo, both diesel fuel only and dual fuel (DF) operations. The results show that 86 % NG could be substituted for diesel fuel at low speeds over the whole load range. Maximum IfG operotion showed higher corbon monoxide (CO) emissions than the diesel fuel only operution while smoke was reduced with DF operation. The maximum vulues of smoke emission were 30 Hutridge smoke numbers (HSIV) with the maximum IfG and 28.5 HSIY in diesel fael only opeFation

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