LIGHT EMITTING DIODES (LEDS) WITH IMPROVED LIGHT EXTRACTION BY ROUGHENING

• US 20110101400A1
• Filed: 01/07/2011
• Published: 05/05/2011
• Est. Priority Date: 01/11/2005
• Status: Active Grant

• Current Assignee: Semileds Optoelectronics Company Limited (SemiLEDs Inc)
• Original Assignee: Semileds Optoelectronics Company Limited (SemiLEDs Inc)
• Inventors: Fan, Feng-Hsu, Cheng, Chao-Chen, Cheng, Hao-Chun, Liu, Wen-Huang, CHU, CHEN-FU
• Granted Patent: US 8,466,479 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers

Abstract

Systems and methods are disclosed for fabricating a semiconductor light-emitting diode (LED) device by forming an n-doped gallium nitride (n-GaN) layer on the LED device and roughening the surface of the n-GaN layer to extract light from an interior of the LED device.

Claims

1. A light-emitting diode (LED) structure, comprising:

a multilayer semiconductor structure for emitting light, a surface of the structure having a plurality of protuberances, wherein lateral surfaces of the protuberances form an angle greater than 90°

with the surface of the multilayer semiconductor structure and wherein the surface of the structure and the protuberances are roughened or textured for increased surface area.

2. The LED structure of claim 1, wherein the surface of the structure and the protuberances are textured with polystyrene spheres.

3. The LED structure of claim 1, wherein the multilayer semiconductor structure comprises:

a p-doped layer;

an active layer for emitting light disposed above the p-doped layer; and

an n-doped layer disposed above the active layer, such that the surface of the structure having the plurality of protuberances is a surface of the n-doped layer.

4. The LED structure of claim 1, further comprising a conductive substrate disposed beneath the multilayer semiconductor structure.