High-reflectance III-nitride distributed Bragg reflectors grown on Si substrates

Distributed Bragg reflectors (DBRs) composed of an AlN∕AlGaN superlattice were grown of Si (111) substrates. The first high-reflectance III-nitride DBR on Si was achieved by growing the DBR directly on the Si substrate to enhance the overall reflectance due to the high index of refraction contrast at the Si∕AlN interface. For a 9× DBR, the measured peak reflectance of 96.8% actually exceeded the theoretical value of 96.1%. The AlN∕AlGaN …