The GaN/substrate bi layer may be cooled from the growth temperature to an ambient temperature, wherein {HEAD ~ GaN material cracks} laterally and separates from {TAIL ~ the substrate}, forming a free standing article 
laterally
The GaN / substrate bi layer may be cooled from the growth temperature to an ambient temperature , wherein { HEAD ~ GaN material cracks } laterally and separates from { TAIL ~ the substrate } , forming a free standing article
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH