US Patent 11588299 Vertical-cavity surface-emitting laser fabrication on large wafer

Methods for fabricating vertical cavity surface emitting lasers (VCSELs) on a large wafer are provided. An un-patterned epi layer form is bonded onto a first reflector form. The first reflector form includes a first reflector layer and a wafer of a first substrate type. The un-patterned epi layer form includes a plurality of un-patterned layers on a wafer of a second substrate type. The first and second substrate types have different thermal expansion coefficients. A resulting bonded blank is substantially non-varying in a plane that is normal to an intended emission direction of the VCSEL. A first regrowth is performed to form first regrowth layers, some of which are patterned to form a tunnel junction pattern. A second regrowth is performed to form second regrowth layers. A second reflector form is bonded onto the second regrowth layers, wherein the second reflector form includes a second reflector layer.