Large-area, liftoff nanoporous GaN distributed Bragg reflectors: Fabrication and application
Abstract
A facile one-step electrochemical etching based on NaNO3 solution was developed for use in the chemical lift-off nanoporous- (NP-) GaN distributed Bragg reflectors (DBRs) over a macroscopic area (>1 cm2). The reflectivity of the lift-off DBR mirror is 85%, which is far lower than that ( 97%) of the NP-GaN DBR on the sapphire substrate. The decrease should be attributed to light scattering due to higher roughness in the lift-off mirror. To study its possible applications, tris(8-hydroxyquinoline) aluminum (III) (Alq3) thin film was grown on transferred NP-GaN DBR mirror onto silicon substrate via a thermal evaporation deposition. Compared to the reference Alq3 thin film, the photoluminescence of the Alq3 thin film on the transferred mirror presents significant enhancement and slight blue-shift, which should be attributable to reflectivity enhancement by the DBR and inner channel surface in the DBR mirror, respectively.
- Publication:
-
Applied Surface Science
- Pub Date:
- September 2019
- DOI:
- 10.1016/j.apsusc.2019.05.128
- Bibcode:
- 2019ApSS..489..849Y
- Keywords:
-
- Nanoporous GaN;
- DBR;
- Lift-off;
- Transferred;
- Alq<SUB>3</SUB> thin film