Effect of Top-Region Area of Flat-Top Pyramid Patterned Sapphire Substrate on the Optoelectronic Performance of GaN-Based Light-Emitting Diodes

Figure 2

Cross-sectional SEM image of (a) FTP-PSS-A, (b) FTP-PSS-B, and (c) FTP-PSS-C. Top-view SEM images of (d) FTP-PSS-A, (e) FTP-PSS-B, and (f) FTP-PSS-C.

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