GaN-based LED

摘要

A GaN-based LED includes: a substrate with front and back sides; an epitaxial layer formed over the front side of the substrate and including, from top down, a P-type layer, a light-emitting area, and an N-type layer; a current spreading layer formed over the P-type layer; a P electrode formed over the current spreading layer; a first reflecting layer between the current spreading layer and the epitaxial layer, disposed at a peripheral area of the epitaxial layer in a band-shaped distribution; and a second reflecting layer over the back side the substrate. The band-shaped or annular distribution can increase a probability light extraction of the LED sideways. By controlling the ratio of lights extracted upwards and sideways, the light-emitting distribution evenness can be adjusted and the uneven heat dissipation can be improved.

主权项

1. A GaN-based LED, comprising:
a substrate with front and back sides; an epitaxial layer formed over the front side of the substrate and including, from top down, a P-type layer, a light-emitting area, and an N-type layer; a current spreading layer formed over the P-type layer; a P electrode formed over the current spreading layer; a first reflecting layer between the current spreading layer and the epitaxial layer, disposed at a peripheral area of the epitaxial layer in a band-shaped distribution, and configured to reflect a portion of light emitted upward from the light-emitting area toward at least two sides of the LED to increase light extraction sideways and thereby improve a light distribution evenness; and a second reflecting layer over the back side the substrate.