A vertical cavity surface emitting laser (VCSEL) structure includes a
bottom distributed Bragg reflector (DBR) arranged over a substrate; a
metal layer interposed between the bottom DBR and the substrate, wherein
the metal layer and bottom DBR form a composite mirror structure. A
patterned dielectric layer may be interposed between the metal layer and
the bottom DBR to reduce a deleterious chemical reaction between the
metal layer and the bottom DBR. The metal layer directly contacts a
portion of the bottom DBR to enhance the electrical and thermal
conductivity of the VCSEL structure.