HIGH PERFORMANCE QUANTUM WELL GaAs DISTRIBUTED FEEDBACK AND REFLECTOR STRUCTURES
Original Publication Date: 1989-May-01
Included in the Prior Art Database: 2005-Jan-28
Distributed feedback (DFB) and reflector (DBR) semiconductor lasers with periodic perturbation in refractive index along a waveguide are of interest for single frequency and surface emitting lasers. The fabrication of these structures is usually very complicated and involves a difficult regrowth step to overgrow on top of a grating patterned on a laser. The figure illustrates a laser structure which eliminates the need for the material regrowth step. The various layers, deposited on gratings formed at the substrate surface, can be grown by molecular beam epitaxy (MBE) many times thicker than the depth of the initial grooves with only negligible planarization if the initial groove shape and growth are optimized.