Controlled Coalescence of AlGaN Nanowire Arrays: An Architecture for Nearly Dislocation-Free Planar Ultraviolet Photonic Device Applications

Nearly dislocation‐free semipolar AlGaN templates are achieved on c‐plane sapphire substrate through controlled nanowire coalescence by selective‐area epitaxy. The coalesced Mg‐doped AlGaN layers exhibit superior charge‐carrier‐transport properties. Semipolar‐AlGaN ultraviolet light‐emitting diodes demonstrate excellent performance. This work establishes the use of engineered nanowire structures as a viable architecture to achieve large‐area, dislocation‐free planar photonic and electronic devices.