Abstract: An organic light-emitting diode display may have thin-film transistor circuitry formed on a substrate. A pixel definition layer may be formed on the thin-film transistor circuitry. Openings in the pixel definition layer may be provided with emissive material overlapping respective anodes for organic light-emitting diodes. A cathode layer covers the array of pixels. Patterned metal on the pixel definition layer may assist the cathode layer in distributing a power supply voltage to the organic light-emitting diodes. The patterned metal may be overlapped by patterned black masking material on an encapsulation layer such as a color filter layer. The pixel definition layer may also be formed from metal that is coated with inorganic dielectric. The cathode may be shorted to a metal pixel definition layer through openings in the inorganic coating.

Abstract: An evaporation tool is provided that has an elongated evaporation source with elongated edges that run parallel to a longitudinal axis and shorter edges that run perpendicular to the longitudinal axis. The evaporation source has multiple evaporation sources formed by respective source orifices through which material is evaporated. An evaporation control structure is mounted to the evaporation source to enhance the directionality of evaporated material. A shadow mask is provided that has a rectangular frame for supporting a metal mask layer with a pattern of openings. The evaporation control structure ensures that the evaporated material from the source is evaporated towards the shadow mask. Angled walls attached to the elongated edges, a series of vertical walls that extend between the angled walls in the evaporation control structure, and aligned vertical wall extensions on the frame of the shadow mask are used to block evaporated material following angled trajectories.