Abstract |
Characteristics of etching and induced surface morphology variation by wet-etching of n-face ntype GaN were investigated using KOH solutions. It was observed that hexagonal pyramids were formed on the etched surface regardless of etching conditions. However, the size of the hexagonal pyramids was changed as the etching time and temperature increased, respectively. Initially, as the etching time and concentration of KOH solution increased, the hexagonal pyramid was observed to be dissociated into smaller pyramids. However, as the etching time increased further, the size of the hexagonal pyramids increased again, indicating that the etching of N-face n-type GaN by KOH solutions proceeded through the evolution of hexagonal pyramids, such as formation, dissociation and enlargement of pyramids. Furthermore, it was also observed that there is a correlation between the photoluminescence intensity of the etched surface and the value of rootmean- square roughness. The intensity of PL increased as the roughness value increased due to the enhancement of the extraction efficiency of the generated photons. |
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Key Words |
wet etch, n-face GaN, RMS roughness, KOH |
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