Defect Passivation by Nanospheres Using H3PO4 and KOH Etching for UV LED

• Main Authors: Ma, Ying-Tsung, 馬印聰
• Other Authors: Lin, Chien-Chung
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/06276536655924809868

碩士 === 國立交通大學 === 光電系統研究所 === 100 === In this thesis, we compared defect passivation process by using H3PO4 and KOH etching solution. We observed GaN etching morphology.The H3PO4 prefer to etch screw type dislocation which is treated as non-radiative centers. On the other hand, KOH prefer to attack edge type dislocation. We simplified the defect passivation process by using silica nanospheres as blocking material, which is much cheaper and convenience than using plasma-enhanced chemical vapor deposition. By blocking the non-radiative centers, the internal quantum efficiency has been enhanced 17.1%. The reflection of embedded silica nanospheres were enhanced about 2% in 361nm wavelength, which verified the silica nanosphere could act as reflector in ultraviolet.