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We report a low temperature fabrication and light-emitting characteristics of inorganic electroluminescent (EL) devices in which a CdSe/ZnS quantum dot (QD) layer was formed by a new ion beam deposition process. The deposition process was developed for fabrication of surfactant- and solvent-free QD structured films from colloidally dispersed QD solution. The electroluminescence spectra of the alternating field driven devices were found to be identical to the photoluminescence spectra of the source solution. The finding paves the way for the development of full color, transparent, flexible, and low-cost large area flat panel displays.

White organic electroluminescent devices fabricated using the ink-jet printing method have been investigated. The solution of organic materials was composed of a hole transport material, an electron transport material and an emission material dissolved in 1,2-dichloroethane. A maximum luminance of 3,600 cd/m2, maximum external quantum efficiency of 4.15% and Commission International de l'Eclairage chromaticity of (x,y)=(0.29,0.33) have been obtained from the device with poly(9-vinylcarbazole) as host material, 2,5-bis(1-naphthyl)-1,3,4-oxadiazole as electron transport material, a mixture of perylene and 4-dicyanomethylene-6-cp-julolidinostyryl-2-tert-butyl-4H-pyran as emission materials, and cesium as cathode.

The self-aligned bank formation of organic electroluminescent devices using the ink-jet printing method was proposed and investigated. A solution of organic materials mixed with host and emission materials was printed on an indium–tin–oxide-coated glass substrate covered with an insulating polymer layer. The insulating material was dissolved in a solvent, and a mixture of organic materials was formed at the same position as that of the ink-jet-printed region, that is, a self-aligned organic electroluminescent device was realized. The diameter of the emission region was 200 µm and a luminance of 9,070 cd/m2 was obtained using an electrophosphorescent material.

The light out-coupling properties of inorganic thin-film electroluminescent devices can be improved by using a new device structure with a light-scattering layer. This consists of particles dispersed in a binder and it can be laminated on the surface of conventional devices by screen-printing. The light-scattering layer increases the luminance to approximately three times that of conventional devices and reduces the viewing-angle dependence of the electroluminescent spectrum.

A color-variable electroluminescent diode has been realized utilizing a 1-nm-thick dye molecule layer with single-quantum-well (SQW) structure. The electroluminescent (EL) spectrum changes with increasing applied voltage from 8 V to 20 V. The result is discussed in terms of the shift of the recombination region toward the ITO electrode, depending on applied voltage.

A novel display device combining a polymer-dispersed liquid crystal (PDLC) film and a thin-film electroluminescent (TFEL) device was fabricated. This device may be used as a liquid crystal display (LCD) in strong light ambient. In the dark, it can be switched to become an electroluminescent display, providing high viewability. Measurements of its electrooptical characteristics showed that the breakdown voltage of the TFEL device did not change significantly with the addition of a LC layer. It implies that the cured polymer could provide an intrinsic barrier preventing LC material from diffusing into the TFEL device.

Electron cyclotron resonance hydrogen plasma reactive ion etching (RIE) with n-butyl acetate reactive gas has been demonstrated. The etching mechanism is discussed for RIE of transparent conducting oxide films. The RIE technique exhibits excellent material selectivity resulting from the ability to control the etching mechanism by altering the accelerating voltage frequency. To demonstrate the practical application of RIE, an electroluminescent display fabrication is described.

The d.c. and pulsed current give rise to an electroluminescent phenomenon in both of α- and β-SiC crystals. The α-crystals are composed of p–in–n junction along their c-axis and the light emission under forward bias takes place in the n-type region. The emission is conceived to originate from the emission centers in the n-type layer excited by the diffusion current flowing into the layer.