GaN substrate and GaN homo-epitaxy for LEDs: Progress and challenges<xref ref-type="fn" rid="cpb150941fn1">*</xref>

GaN substrate and GaN homo-epitaxy for LEDs: Progress and challenges*

Wu Jie-Jun, Wang Kun, Yu Tong-Jun†, Zhang Guo-Yi

Schematic diagrams of the location of three wafers (red dashed line circles) on the substrate holder and their thick film ribbons (blue area) variations [(a)–(c)] and their relatively measured thickness distribution mapping for one wafer [(d)–(f)] grown under different ID gas flow rate of 8 slm [(a) and (d)], 11 slm [(b) and (e)], and 14.6 slm [(c) and (f)]. Schematic illustration of ID-PMG method (g) and thickness mapping of GaN layer for one of three wafers grown by ID-PMG method (h).^{[ 43 ]}