Stress relaxation in the GaN/AIN multilayers grown on a mesh-patterned Si(111) substrate

A large crack-free size of the GaN/AlN multilayers is expitaxially grown on the Si(111) substrate patterned with the Si(sub x)N(sub y) mesh. The stress relaxation is mainly attributed to the existence of the free surfaces (1011), (1122) and (1101) and the thermal-expansion coefficient difference among Si(sub x)N(sub y), GaN/AlN, and Si.