TANDEM ELECTROLUMINESCENT DEVICE WITH IMPROVED RESOLUTION AND RELIABILITY

Abstract

Electroluminescent display device (300) comprising a pixel matrix, each pixel (313) having at least one sub-pixel (301a, 301b, 301c) having a control electrode (302a, 302b, 302c) coated with a conductive layer (330), and a tandem OLED stack (305) comprising at least two OLED stacks (331, 333), the first (331) being deposited on said conductive layer (330) of the control electrode, and on the second being deposited an upper electrode (306), said device being characterized in that: - the space (311) between two adjacent control electrodes has the shape of a trench, - the surface of said trench has a dielectric layer (323) which covers the vertical sides of the control electrodes,- said dielectric layer forms a rim (312) on said control electrode to form a step of a height (h) at least equal to the thickness (e) of the first charge carrier transport layer (3313) of the first OLED stack. [Figure 10]

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