Light Emitting Diode (LED) Devices With Nucleation Layer

Abstract

Described are light emitting diode (LED) devices having patterned substrates and methods for effectively growing epitaxial III-nitride layers on them. A nucleation layer, comprising a III-nitride material, is grown on a substrate before any patterning takes place. The nucleation layer results in growth of smooth coalesced III-nitride layers over the patterns.

What is claimed is: 
     
         1 . A light emitting diode device comprising:
 a patterned substrate comprising a substrate body, a plurality of integral features protruding from the substrate body, and a base surface defined by a plurality of voids between the plurality of integral features, the plurality of integral features having a top surface and sidewalls and a height, a pitch, and a width;   a nucleation layer on a top surface of the plurality of integral features and not in the plurality of voids, the nucleation layer comprising a first III-nitride material; and   a III-nitride layer on the nucleation layer, the III-nitride layer comprising a second III-nitride material.   
     
     
         2 . The light emitting diode device of  claim 1 , wherein the first III-nitride material and the second III-nitride material independently comprise one or more of aluminum, gallium, and indium. 
     
     
         3 . The light emitting diode device of  claim 2 , wherein the first III-nitride material comprises aluminum nitride (AlN). 
     
     
         4 . The light emitting diode device of  claim 2 , wherein the first III-nitride material and the second III-nitride material are the same. 
     
     
         5 . The light emitting diode device of  claim 1 , wherein the second III-nitride material comprises gallium nitride (GaN). 
     
     
         6 . The light emitting diode device of  claim 1 , wherein the nucleation layer has a thickness in a range of from 5 nm to 50 nm. 
     
     
         7 . A method of manufacturing a light emitting diode (LED) device, the method comprising:
 depositing a nucleation layer on a substrate, the nucleation layer comprising a first III-nitride material;   patterning the substrate to form a plurality of nucleation layer-coated substrate posts separated by the plurality of voids; and   epitaxially growing the III-nitride layer on the plurality of nucleation layer-coated substrate posts, the III-nitride layer comprising a second III-nitride material.   
     
     
         8 . The method of  claim 7 , wherein the first III-nitride material and the second III-nitride material independently comprise one or more of aluminum, gallium, and indium. 
     
     
         9 . The method of  claim 8 , wherein the first III-nitride material comprises aluminum nitride (AlN). 
     
     
         10 . The method of  claim 8 , wherein the first III-nitride material and the second III-nitride material are the same. 
     
     
         11 . The method of  claim 7 , wherein the second III-nitride material comprises gallium nitride (GaN). 
     
     
         12 . The method of  claim 7 , wherein the nucleation layer has a thickness in a range of from 5 nm to 50 nm.