Study On 976nm Tapered Semiconductor Laser Technology

High power and high beam quality semiconductor lasers have been widely used in the fields of optical pumping,optical communication,material processing and medical treatment.Tapered semiconductor lasers have become one of the hotspots of current research because of their special structures,which have high power and high beam quality.This paper mainly focuses on the design of the 976 nm DBR tapered semiconductor laser.Firstly,an asymmetric waveguide dual quantum well epitaxial structure with an optical confinement factor ? of less than 2% is designed to suppress the self-focusing and filament phenomenon of tapered semiconductor laser.Compared with the single quantum well epitaxial structure with the same ?,the designed epitaxial structure can increase the inject tapered region optical power by 9%,and the distribution of the diffraction intensity of the fundamental lateral mode in the tapered region is more uniform.Secondly,according to the diffractive characteristics of the fundamental lateral mode in the device,the structural parameters of the ridge waveguide and the tapered region are optimized,and the structural parameters of the first-order DBR grating region are optimized for the reflectivity at 976 nm wavelength.Finally,aiming at the difficulty of aligning ridge waveguides and tapered region in lithography,a set of positive and negative photoresist lithography process schemes were proposed.