Advancements in nanoporous GaN distributed bragg reflectors: a comprehensive review

Abstract Nanoporous Gallium Nitride (GaN) distributed Bragg reflectors (DBRs) have emerged as a promising component in advanced optical devices, offering significant improvements in performance due to their unique structural and optical properties. This review provides a comprehensive overview of the recent progress in the properties, fabrication techniques, and application of nanoporous GaN DBRs. It highlights the limitations of conventional GaN DBRs and validates how nanoporous structures can effectively address these challenges. Various fabrication methods, such as metal-organic chemical vapor deposition, molecular beam epitaxy, electrochemical etching, and photoelectrochemical etching, are analyzed in detail along with their challenges. The article focuses on the effects of electrolytes, applied voltage, doping density, and etching parameters on pore size and porous morphology. The review further investigates the impact of nanoporous structures on the reflectivity and bandwidth of the DBRs, supported by a comparative analysis with traditional DBRs. Current and emerging applications in optical filters, photonic devices, light-emitting diodes, and lasers are explored. The discussion on the potential of nanoporous GaN DBRs to advance the future of photonic devices is included. This review aims to serve as a valuable resource for researchers and engineers in the field, providing insights into the advancements and potential of nanoporous GaN DBRs in optical device technology.