Indium gallium nitride smoothing structures for III-nitride devices

A III-nitride light emitting device comprising:

• a substrate;
• an n-type region overlying the substrate;
• an active region overlying the n-type region;
• and
• a graded smoothing region containing indium, the graded smoothing region being located between the substrate and the active region;
• wherein the graded smoothing region comprises a grading superlattice, the grading superlattice comprising:
• a first set of superlattice layers, wherein composition of the first set of superlattice layers changes across the first set of superlattice layers;
• and
• a second set of superlattice layers, wherein composition of the second set of superlattice layers changes across the second set of superlattice layers;
• wherein superlattice layers from the first set alternate with superlattice layers from the second set.

A III-nitride light emitting device comprising:

• a substrate;
• an n-type region overlying the substrate;
• an active region overlying the n-type region;
• and
• a graded smoothing region containing indium, the graded smoothing region being located between the substrate and the active region;
• wherein the smoothing region comprises a graded dopant concentration.