The band gap tuning of amorphous silicon carbon nitride thin (a-SiCN) film was demonstrated in the range of 2.3–3.0 eV by pulsed laser deposition using mixed targets. a-SiCN films were grown on silicon and quartz glass substrates at room temperature in a vacuum. Targets were fabricated by compacting a mixture of silicon carbide and silicon nitride powders. The stoichiometry of the film could be varied by the mixing ratio of the target. Ternary phase SiCN films were deposited at 30– 70 wt. % SiC in a target and their band gaps were controlled by appropriate adjustment of the carbon content. These findings indicate that the growth of a-SiCN films with a mixed target and their subsequent use as optoelectronic materials is a possibility.

Size-dependent charge storage was observed in metal–insulator–semiconductor structures containing amorphous Si quantum dots $\mathrm{(a-}\mathrm{Si}$ QDs) grown by plasma-enhanced chemical vapor deposition. For $\mathrm{a-}\mathrm{Si}$ QDs as large as 2 nm in diameter, one electron or one hole was stored in each $\mathrm{a-}\mathrm{Si}$ QD. For small-sized $\mathrm{a-}\mathrm{Si}$ QDs of 1.4 nm in diameter, however, the width of capacitance–voltage hysteresis was decreased, indicating that the charge density in the $\mathrm{a-}\mathrm{Si}$ QDs was reduced. This can be attributed to the lowered tunneling barrier in the small-sized $\mathrm{a-}\mathrm{Si}$ QDs resulting from a large quantum confinement effect. Long-term charge storage was observed in the fully charged $\mathrm{a-}\mathrm{Si}$ QDs; this is attributed to a suppression of the discharge process by electrostatic repulsion among the charged dots.

High quality indium tin oxide (ITO) thin films were grown by pulse laser deposition (PLD) on flexible polyethersulphone (PES) substrates. The electrical, optical, and surface morphological properties of these films were examined as a function of substrate temperature and oxygen pressure. ITO thin films, deposited by PLD on a PES substrate at room temperature and an oxygen pressure of 15 mTorr, have a low electrical resistivity of 2.9×10⁻⁴ Ω cm and a high optical transmittance of 84 % in the visible range. They were used as the anode in organic light-emitting diodes (OLEDs). The maximum electro luminescence (EL) and current density at 100 cd/m² were 2500 cd/m² and 2 mA/cm², respectively, and the external quantum efficiency of the OLEDs was found to be 2.0 %.

Silicon nanocrystals (Si-NCs) were grown in situ in carbide-based film using a plasma-enhanced chemical vapor deposition method. High-resolution transmission electron microscopy indicates that these nanocrystallites were embedded in an amorphous silicon carbide-based matrix. Electron diffraction pattern analyses revealed that the crystallites have a hexagonal-wurtzite silicon phase structure. The peak position of the photoluminescence can be controlled within a wavelength of 500 to 650 nm by adjusting the flow rate of the silane gas. We suggest that this phenomenon is attributed to the quantum confinement effect of hexagonal Si-NCs in silicon carbide-based film with a change in the sizes and emission states of the NCs.