Evaluation of Distributed Inorganic Electroluminescence (EL) Devices with Comb Electrodes

抄録

Distributed inorganic electroluminescence (EL) devices comprise a metal electrode, and can be fabricated at a low cost using coating processes. In this study, we deposited comb electrodes with narrow gaps between the teeth on a glass substrate, thus realizing a high electric field intensity that cannot be achieved with conventional structures. Au electrodes are deposited to form a comb shape and then spin-coated with a phosphor layer obtained by mixing ZnS phosphor particles with resins at a certain ratio. An AC voltage was applied to the gaps between the teeth of the comb electrode to emit light, from which the luminance was measured for different electric field intensities. The luminances measured from the glass substrate side (the bottom of the device) were low for a device with a Au comb electrodes (Au electrodes) when the electric field intensity was 15 V/μm. However, the luminances measured from the phosphor layer side (the top of the device) for the device with the Au electrodes were high. In contrast, the luminance measured from the phosphor layer side for the device with the Au electrodes 1.5-fold higher than that measured from the glass substrate side. This was because the luminance was not affected by the transmittance of the electrodes themselves when measured from the phosphor layer side. Therefore, it may be possible to produce a display that does not require transparent electrodes by using the phosphor layer side of a device with comb electrodes made of metals, such as Au, for the front side of the display.