Patent ID: 7528055

Claim:
A method of producing nitride semiconductor devices comprising the steps of: preparing an Al x In y Ga 1-x-y N (0≦x≦1; 0≦y≦1; 0≦x+y≦1) defect position controlled substrate S including a closed loop network defect accumulating region H and low defect density regions ZY enclosed by the closed loop network defect accumulating region H, growing epitaxially Al uj In vj Ga 1-uj-vj N (0≦uj≦1; 0≦vj≦1; 0≦uj+vj≦1) upper layers selectively on the low defect density regions ZY, forming upper layer parts B on the low defect density regions ZY, dissolving bottom parts of the upper layer parts B, separating the upper layer parts B as device chips C from the defect position controlled substrate S in a vertical direction, simultaneously separating the upper layer parts B from each other in horizontal directions, and reusing the defect position controlled substrate S as a substrate for a next production.