On the use of tin oxide for metal-dielectric mirrors with strong adhesion

Many optical devices, but particularly vertical-cavity surface emitting lasers (VCSEL's), require high reflectivity mirrors. These mirrors are typically stacks of quarter-wavelength thick layers (as measured in the material), of alternating high and low index layers, placed on the device either by epitaxial techniques, or by dielectric deposition techniques such as evaporation. For bottom emitters, the thickness of these mirrors can be greatly reduced by capping the stack with a low optical loss metal (the thickness of the last dielectric layer would be adjusted for optical phase matching).