PURPOSE: To maintain high coloring efficiency and to provide higher adhesion strength between respective layers constituting a thin film type EC display element and a long life by forming the respective layers by sputtering in oxygen or a gaseous mixture composed of oxygen and inert gas.
CONSTITUTION: The respective layers of an EC display element constituted by laminating an n type EC layer 3, an electrolyte layer 4 and a p type EC layer 5 are formed by sputtering targets consisting of units or oxides of the respective constituting metallic elements in oxygen or a gaseous mixture composed of oxygen and inert gas. W and WOx, Ta or Ta2O5 and Ir or IrOx are respectively used as the targets for forming the n type EC layer 3, the electrolyte layer 4 and the p type EC layer 5. The film formed by sputtering using such targets have high adhesion strength to the underlying layers and since all the films are formed by sputtering, the secure laminated structure is obtd. The exfoliation of the films during operation is thus obviated, by which the decrease in display quality and defective operation is eliminated. coloring responsiveness and coloring density, etc. are good as well and the reliability in manufacture and use is improved.
KOIKE YOSHIROU
WATANABE MASANORI
HORI KENICHI
