Composite high reflectivity layer

US7915629B2 · kind B2 · utility

Assignee

• Cree, Inc. · US

Inventors

• Ting Li · Ventura, US
• Monica Hansen · Lompoc, US
• James Ibbetson · Lompoc, US

Key dates

• Filing date: Dec 8, 2008
• Grant date: Mar 29, 2011
• Expiry date: Apr 8, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2224/48247

Abstract

A high efficiency light emitting diode with a composite high reflectivity layer integral to said LED to improve emission efficiency. One embodiment of a light emitting diode (LED) chip comprises an LED and a composite high reflectivity layer integral to the LED to reflect light emitted from the active region. The composite layer comprises a first layer, and alternating plurality of second and third layers on the first layer, and a reflective layer on the topmost of said plurality of second and third layers. The second and third layers have a different index of refraction, and the first layer is at least three times thicker than the thickest of the second and third layers. For composite layers internal to the LED chip, conductive vias can be included through the composite layer to allow an electrical signal to pass through the composite layer to the LED.