High density pixelated-led chips and chip array devices

Abstract

Pixelated-LED chips and related methods are disclosed. A pixelated-LED chip includes an active layer with independently electrically accessible active layer portions arranged on or over a light-transmissive substrate. The active layer portions are configured to illuminate different light-transmissive substrate portions to form pixels. Various enhancements may beneficially provide increased contrast (i.e., reduced cross-talk between pixels) and/or promote inter-pixel illumination homogeneity, without unduly restricting light utilization efficiency. In some aspects, a light extraction surface of each substrate portion includes protruding features and light extraction surface recesses. Lateral borders between different pixels are aligned with selected light extraction surface recesses. In some aspects, selected light extraction surface recesses extend through an entire thickness of the substrate. Other technical benefits may additionally or alternatively be achieved.