Vertical cavity surface emitting laser with integrated diffractive lens and method of fabrication

A vertical cavity surface emitting laser device comprising:

• a substrate having a surface;
• a first stack of distributed Bragg reflectors including a plurality of pairs of alternating layers disposed on the surface of the substrate, the first stack of distributed Bragg reflectors having a surface;
• an active region having a first and a second surface and including an active structure sandwiched between a first cladding region and a second cladding region, the active structure including at least one quantum well structure and a plurality of barrier layers, the active region being lattice matched to the surface of the first stack of distributed Bragg reflectors;
• a second stack of distributed Bragg reflectors lattice matched to the second surface of the active region and including a plurality of pairs of alternating layers, the first stack of distributed Bragg reflectors, the active region and the second stack of distributed Bragg reflectors defining an optical cavity;
• and
• a diffractive planar lens element etched into a layer of silicon nitride (SiN) directly deposited on an uppermost surface of the second stack of distributed Bragg reflectors, and within a path of emission generated by the vertical cavity surface emitting laser, the diffractive planar lens element focusing the emission at a point external the defined optical cavity.