Light emitting regions for use with light emitting devices

Abstract

A light emitting device comprises a first layer having an n-type Group III-V semiconductor, a second layer adjacent to the first layer, the second layer comprising an active material that generates light upon the recombination of electrons and holes. The active material in some cases has one or more V-pits at a density between about 1 V-pit/μm 2 and 30 V-pits/μm 2 . The light emitting device includes a third layer adjacent to the second layer, the third layer comprising a p-type Group III-V semiconductor.

1 - 26 . (canceled) 
     
     
         27 . A method for forming a light emitting diode (LED), comprising:
 forming an n-type or p-type Group III-V semiconductor layer adjacent to an active layer,   wherein the active layer is formed by exposing a substrate to a Group III precursor and a Group V precursor at one or more growth conditions selected to generate one or more V-pits in the active layer, the one or more V-pits having one or more openings at an interface between the active layer and the n-type or p-type Group III-V semiconductor layer, the V-pits having a density between about 10 V-pit/μm 2  and 20 V-pits/μm 2  at the interface and a density between about 10% and 20% of a surface coverage of the interface.   
     
     
         28 . The method of  claim 27 , wherein the Group III-V semiconductor comprises gallium nitride. 
     
     
         29 . The method of  claim 27 , wherein the Group III precursor comprises gallium. 
     
     
         30 . The method of  claim 27 , wherein the Group V precursor comprises nitrogen. 
     
     
         31 . The method of  claim 27 , wherein the Group V precursor is selected from ammonia. 
     
     
         32 . The method of  claim 27 , wherein the active layer is formed at a temperature between about 750° C. and 850° C. 
     
     
         33 . The method of  claim 27 , wherein the active layer is formed at a hydrogen (H 2 ) flow rate between about 1 liter/minute and 20 liters/minute. 
     
     
         34 . The method of  claim 27 , wherein the substrate comprises silicon. 
     
     
         35 . A method for forming a light emitting diode (LED), comprising:
 forming an active layer by exposing a substrate in a reaction chamber to a Group III precursor and a Group V precursor to form an active layer having one or more V-pits at a density between about 1 V-pit/μm 2  and 30 V-pits/μm 2 ,   wherein, during the formation of the active layer:   i) the temperature of the substrate is between about 750° C. and 850° C.; and/or   ii) the flow rate of hydrogen (H 2 ) into the reaction chamber is less than or equal to about 20 liters/minute.   
     
     
         36 . The method of  claim 35 , wherein the substrate comprises a layer of an n-type or p-type Group III-V material, and the active layer is formed over the layer of the n-type of p-type Group III-V material. 
     
     
         37 . A method for forming a light emitting diode (LED), comprising:
 providing a substrate in a reaction chamber;   forming a quantum well layer adjacent to the substrate by directing into the reaction chamber a Group III precursor and a Group V precursor, wherein the quantum well layer is formed at a growth temperature between about 750° C. and 790° C.; and   forming a barrier layer adjacent to the quantum well layer by directing into the reaction chamber the Group III precursor and the Group V precursor, wherein the barrier layer is formed at a growth temperature between about 790° C. and 850° C., wherein the barrier layer is formed with a donor material.   
     
     
         38 . The method of  claim 37 , wherein the substrate comprises silicon. 
     
     
         39 . The method of  claim 37 , wherein the barrier layer is formed at a hydrogen (H 2 ) flow rate between about 1 liter/minute and 20 liters/minute. 
     
     
         40 . The method of  claim 35 , further comprising forming an n-type or p-type Group III-V semiconductor layer over the active layer, wherein the one or more V-pits having one or more openings at an interface between the active layer and the n-type or p-type Group III-V semiconductor layer, the V-pits having a density between about 10 V-pit/μm 2  and 20 V-pits/μm 2  at the interface and a density between about 10% and 20% of a surface coverage of the interface.