Patent ID: 6589805
Filing Date: 2003-07-08
Classification: H01S,H04B

Abstract:
A method of fabricating a current confinement structure into a partially-constructed VCSEL, said partially-constructed VCSEL having an active layer disposed between an upper set of material layers thereabove and a lower set of material layers therebelow, said partially-constructed VCSEL further comprising a current confinement layer positioned below the upper set of material layers and immediately above the active layer, comprising:forming at least three hollow vertical shafts extending downward from a top surface of the upper set of material layers to at least a bottom of the current confinement layer, the vertical shafts being laterally positioned outside a desired current confinement zone; and etching with a selective etchant that laterally etches the current confinement layer substantially faster than it etches any of the upper material layers and substantially faster than it etches the active layer, the current confinement layer thereby being etched away outwardly from an axis of each vertical shaft so as to form a subsurface void around each hollow vertical shaft at the current confinement layer, said etching continuing until the subsurface cavities merge together to form a single subsurface circumferential cavity around the desired current confinement zone.