Department of Materials Science and Engineering;
Pohang University of Science and Technology;
Pohang 790-784;
Korea;
LED Business;
Samsung Electronics;
Yongin 446-920;
Korea;
Future Chips Constellation;
Department of Electrical;
Computer;
and Systems Engineering;
Rensselaer Polytechnic Institute;
Troy;
NY 12180;
USA;
deep ultraviolet; light-emitting diodes; light-extraction efficiency;