Patent ID: 7860137
Filing Date: 2010-12-28
Classification: H01S

Abstract:
1. A VCSEL comprising a substrate of a first conductivity type and an epitaxial structure, wherein the epitaxial structure comprises: a bottom DBR mirror disposed on the substrate wherein the bottom mirror is doped to the first conductivity type and wherein the bottom DBR mirror comprises alternating layers of AlAs and GaAs with ramps between the AlAs and GaAs layers, the ramps including a step change to AlGaAs with at least 30% aluminum and an essentially continuous ramp of decreasing aluminum composition between the step change and the GaAs layer; an active layer disposed on the bottom mirror that contains quantum wells; a periodically doped first conduction layer of a second conductivity type, the first conduction layer at least partially contacting the active layer, the doped first conduction layer being heavily doped at a location where the optical electric field is at about a minimum; an aperture formed in the epitaxial structure above the quantum wells; and a thermally conductive top mirror coupled to the periodically doped first conduction layer, the top mirror forming a mesa structure having a lateral wall, wherein the top mirror is essentially undoped, the top mirror having alternating layers that are substantially non-graded at an interface between the alternating layers so as to increase heat conduction through the top mirror; a thermally conductive intra-cavity contact layer having a first portion that is deposited on the first conduction layer an a second portion formed above the first portion wherein the second portion completely covers the lateral wall of the mesa structure and at least partially covers the top of the mesa structure so as to conduct heat from the mesa structure, wherein the second portion does not block the aperture; and the active region, top mirror, and bottom mirror configured to emit a laser beam from the top mirror.