LAUSR

Well-aligned lateral oriented and vertical oriented nanoporous GaN were fabricated by electrochemical etching procedure, and its influence on the optical characteristics of ultraviolet-A multiple quantum well structure was investigated. We used a multiple quantum well structure with V-defect and n-Al0.1Ga0.9N layer, which greatly improved the uniformity of vertical electrochemical etching. Compared to the as-grown multiple quantum well structure, the lateral and vertical oriented nanoporous multiple quantum well structures have 3.8-fold and 8.1-fold photoluminescence intensity enhancement, and the full width at half maximum has been narrowed down from 18.4 nm to 7.9 nm and 2.8 nm, respectively. The vertical oriented nanoporous multiple quantum well structure has a rectangular far-field emission pattern with uniform forward light distribution, and the view angles of 85% intensity is 50 °. This study provides an effective method for improving the light output and controlling the emission angle of GaN based light emitting devices, as well as a method for preparing well-aligned nanopores in semiconductors.