DBR mirrors, and vertical cavity surface emitting lasers that incorporate
such mirrors, comprised of stacked, multiple levels of different
materials having different etching rates for a selected etchant and
etching method. Such DBRs are fabricated by etching an upper level(s)
down to a lower level(s) to form a pillar or trenched structure,
beneficially having an aperture, that has predetermined optical
characteristics. When part of a vertical cavity surface emitting laser, a
lower level can include an ion-implanted region that optionally extends
into an active region and into a bottom DBR.