THIN FILM EL ELEMENT AND METHOD OF MAKING THE SAME

PROBLEM TO BE SOLVED: To provide a thin film EL element in which an uneven structure is provided in a support substrate, achieving both improvement of light extraction efficiency and stabilization of light emission characteristics; and a method of manufacturing the same.SOLUTION: (1) A thin film EL element includes a laminate structure having at least a support substrate, a conductive layer, an isolation layer, and a luminous layer. Periodic projections each having a cross-section in a substantially hemispheric or conical shape are provided on a surface of the support substrate on a side in contact with the conductive layer. Periodic steps are provided on inclined surfaces of each of the projections. (2) A method of manufacturing the thin film EL element described in (1) includes: a support substrate processing step including a resist mask forming step and an etching step; and a thin film forming step. In the etching step, a condition for etching a resist mask and a condition for etching the support substrate are alternately switched to form the periodic projections each having a cross-section in a substantially hemispheric or conical shape, and each having the periodic steps provided on the inclined surfaces of the projection.