Wurtzite III-nitride distributed Bragg reflectors on Si (100) substrates

Understand

Distributed Bragg reflectors (DBRs) composed of an AlN/GaN superlattice were demonstrated for the first time on Si (100) substrates.

• Single-crystal wurtzite superlattice structures were achieved on this cubic substrate by employing offcut Si (100) wafers with the surface normal pointing 4{\deg} towards the [110] direction.
• This misorientation introduced an additional epitaxial constraint that prevented the growth of a two-domain GaN surface as well as cubic GaN inclusions.
• A crack-free 600 nm GaN cap / 5x AlN / GaN DBR structure on Si (100) was demonstrated.