A freestanding GaN single crystal substrate is made by the steps of preparing a (111) GaAs single crystal substrate, forming a mask having periodically arranged windows on the (111) GaAs substrate, making thin GaN buffer layers on the GaAs substrate in the windows of the mask, growing a GaN epitaxial...http://www.google.com.au/patents/US6413627?utm_source=gb-gplus-sharePatent US6413627 - GaN single crystal substrate and method of producing same
