Scalable LED with improved current spreading structures

US6885036B2 · kind B2 · utility

Assignee

• Cree, Inc. · US

Inventors

• Eric Tarsa · Goleta, US
• Brian Thibeault · Lompoc, US
• James Ibbetson · Lompoc, US
• Michael Mack · San Diego, US

Key dates

• Filing date: Jun 25, 2003
• Grant date: Apr 26, 2005
• Expiry date: Jun 25, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H20/858

Abstract

An LED with improved current spreading structures that provide enhanced current injection into the LED's active layer, improving its power and luminous flux. The current spreading structures can be used in LEDs larger than conventional LEDs while maintaining the enhanced current injection. The invention is particularly applicable to LEDs having insulating substrates but can also reduce the series resistance of LEDs having conductive substrates. The improved structures comprise conductive fingers that form cooperating conductive paths that ensure that current spreads from the p-type and n-type contacts into the fingers and uniformly spreads though the oppositely doped layers. The current then spreads to the active layer to uniformly inject electrons and holes throughout the active layer, which recombine to emit light.