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We present the results of a systematic study of chemical vapor deposition of graphene on silicon substrates. The silicon substrate is covered with SiO 2 and capped with an electron-beam evaporator deposited nickel film, which serves as the catalyst for carbon precursor decomposition. Methane is used as the carbon precursor. Three key parameters of CVD growths, the growth temperature, time, and the post-growth cooling rate are studied and the optimized combination of the three allowed for the reproducible fabrication of single layer graphene of larger than 100 μm 2 covering more than 50% of the surface of 1-in. diameter Si wafers. We further demonstrate the transfer of CVD graphene onto SiO 2 /Si surfaces with higher than 95% success rate. Our result together with those reported by other research groups shows real promise of the integration of carbon electronics with silicon integrated circuit technology.

A large-grain polycrystalline silicon film was obtained on a plastic substrate by sequential lateral solidification. With various combinations of sputtering powers and Ar working gas pressures, the conditions for producing dense amorphous silicon (a-Si) and SiO2 films were optimized. The successful crystallization of the a-Si film is attributed to the production of a dense a-Si film that has low argon content and can endure high-intensity laser irradiation.

Indium tin oxide (ITO) films were prepared by radio frequency magnetron sputtering at room temperature, for use as a cathode in a transparent organic light-emitting diode (TOLED). To minimize damage to the TOLED by the ITO sputtering process, the target-to-substrate distance was increased to 20 cm. An ITO film deposited at the optimum oxygen partial pressure exhibited an electrical resistivity as low as 4.06 × 10− 4 Ω cm and a high optical transmittance of 91% in the visible range. The film was used as a transparent cathode for a TOLED with structure of an ITO coated glass substrate / Naphthylphenyldiamide (60 nm) / Tris–(8-hydroxyquinoline) aluminum (60 nm) / LiF (1 nm) / Al (2 nm) / Ag (8 nm) / ITO cathode (100 nm). A maximum luminance of 37,000 cd/m2 was obtained. The device performance was comparable to a conventional OLED.

The effects of a wet chemical surface treatment of molybdenum-tip (Mo-tip) emitters on the electrical characteristics of an active matrix cathode composed of hydrogenated amorphous silicon thin film transistors and Mo-tip emitters are described. X-Ray photoelectron spectroscopy measurements showed that the surface treatment removed MoO 3 from the surface of the e-beam evaporated Mo film. In addition, the surface roughness of the Mo film was increased as the result of the surface treatment. The surface-treated active matrix cathode showed stable emission characteristics and immunity from emitter failures during its operation. The response time of the active matrix cathode was decreased by the surface treatment of the Mo-tip emitters. A change in surface composition and surface roughness appear to be responsible for the enhancement of the active matrix cathode.

We have made an excimer laser annealed poly-Si thin film transistor (TFT). The stress of the poly-Si films crystallized by excimer laser annealing is studied by Raman spectroscopy. The transverse-optic phonon frequency is independent of the excimer laser energy, but dependant on the precursor a-Si film thickness. The nMOS TFT with a self-aligned lightly doped drain (LDD) structure shows low leakage current. The large leakage current of the pMOS TFT with non-LDD structure is reduced by the off-state stress. The gate to channel capacitance as a function of gate voltage for nMOS TFT shows the characteristic parallel shift of the capacitance–voltage curves with frequency variation.

Stable organic white light-emitting diodes are successfully fabricated by a single organic white emitting layer, which is Bis (2-methyl-8-quinolinato) (triphenylsiloxy) aluminum (III) (SAlq) doped red fluorescent dye of 4-(dicyanomethylene)-2- tert -butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4 H -pyran (DCJTB). The incomplete energy transfer from blue-emitting SAlq to red-emitting DCJTB enables to obtain a stable white balanced light-emission by the DCJTB doping concentration of 0.5%. A device with the structure of ITO/TPD (50 nm)/SAlq:DCJTB (30 nm, 0.5%)/Alq 3 (20 nm)/LiF (0.5 nm)/Al (110 nm) shows maximum luminance of 20 400 cd/m 2 at 810 mA/cm 2 , external quantum efficiency of 2% at 200 cd/m 2 (∼3 mA/cm 2 ), power efficiency of 2.3 lm/W at 67 cd/m 2 (∼1 mA/cm 2 ), and a Commission Internationale de l'Eclairage chromaticity coordinates of (0.34, 0.39) at 1.8 mA/cm 2 to (0.31, 0.38) at 36 mA/cm 2 .