1. A monolithically integrated semiconductor device structure comprising: a silicon substrate; a first monocrystalline semiconductor layer disposed over the silicon substrate, wherein the first monocrystalline semiconductor layer has a lattice constant different from a lattice constant of relaxed silicon; an insulating layer disposed over the first monocrystalline semiconductor layer in a first region; a monocrystalline silicon layer disposed over the insulating layer in the first region; at least one silicon-based electronic device comprising an element including at least a portion of the monocrystalline silicon layer; a second monocrystalline semiconductor layer disposed over at least a portion of the first monocrystalline semiconductor layer in a second region and absent from the first region, wherein the second monocrystalline semiconductor layer has a lattice constant different from the lattice constant of relaxed silicon; and at least one III-V light-emitting device comprising an active region including at least a portion of the second monocrystalline semiconductor layer.