Patent · US Active

Microdisplay architecture with light extraction efficiency enhancement

US12300774B2 · kind B2 · utility

0Cited by
2References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 25, 2022
Grant dateMay 13, 2025
Priority date
Expiry dateJun 22, 2043

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10H20/0363
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A light source comprises a backplane wafer with electrical circuits fabricated thereon, and an array of LEDs coupled to the backplane wafer. Each LED of the array of LEDs comprises a mesa structure including semiconductor epitaxial layers and characterized by inwardly tilted mesa sidewalls, a high-refractive index material region (e.g., with a refractive index greater than about 1.75, such as equal to or greater than a refractive index of the semiconductor epitaxial layers) surrounding the semiconductor epitaxial layers of the mesa structure and including outwardly tilted sidewalls, and a reflective layer on the outwardly tilted sidewalls of the high-refractive index material region. In one example, each LED of the array of LEDs also include a passivation layer on the inwardly tilted mesa sidewalls of the mesa structure.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.