Graded slope reflective structures for oled display pixels

A method of fabricating an electroluminescent device, comprising:

• coating a pixel definition layer over a substrate, the pixel definition layer having a bottom surface facing the substrate and a top surface opposite the bottom surface;
• recessing the top surface to form graded sidewalls interconnecting the top and bottom surfaces;
• forming a bottom reflective electrode layer in the recess, the bottom reflective electrode layer including:
• a planar electrode portion disposed over the bottom surface;
• and
• a graded reflective portion disposed over the graded sidewalls, wherein the graded reflective portion has a non-linear profile;
• forming an organic layer over the bottom reflective electrode layer;
• and
• forming a top electrode over the organic layer.

A display structure, comprising:

• an array of electroluminescent devices, each electroluminescent device including:
• a pixel definition layer having a top surface, a bottom surface, and graded sidewalls interconnecting the top and bottom surfaces;
• a bottom reflective electrode layer disposed over the pixel definition layer, the bottom reflective electrode layer including:
• a planar electrode portion disposed over the bottom surface;
• and
• a graded reflective portion disposed over the graded sidewalls, wherein the graded reflective portion has a concave profile;
• an organic layer disposed over the bottom reflective electrode layer;
• and
• a top electrode disposed over the organic layer;
• a plurality of thin-film transistors forming a driving circuit array configured to drive and control the array of electroluminescent devices;
• and
• a plurality of interconnection layers, each interconnection layer in electrical contact between an electroluminescent device and a respective thin-film transistor of the plurality of thin-film transistors.