The first and second electrodes are separately disposed on the epitaxial layer structure, and {TAIL ~ the epitaxial layer structure} has a RMS roughness less than {HEAD ~ 3 nm} on a surface wherein the second electrode is formed 
The first and second electrodes are separately disposed on the epitaxial layer structure , and { TAIL ~ the epitaxial layer structure } has a RMS roughness less than { HEAD ~ 3 nm } on a surface wherein the second electrode is formed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH