1. A method comprising:growing a first III-nitride layer directly on a substrate;
making at least a portion of the first III-nitride layer porous;
growing a second III-nitride layer directly on the porous portion, the second layer comprising InGaN; and
growing a device structure directly on the second III-nitride layer, the device structure comprising a III-nitride light emitting layer disposed between an n-type region and a p-type region.