A method to fabricate an apparatus, said apparatus comprising a substrate (200, 400) and a photonic device (100, 300) with at least a first waveguide (100a, 300a) having a light-conducting core (101, 301) bounded by at least one cladding layer (102, 103, 104, 302, 303), further comprising at least a second waveguide (200a, 400a) having a light-conducting core bounded by at least one cladding layer (202, 203, 204, 402, 403), wherein the first waveguide is aligned to couple with the second waveguide, wherein alignment of the first waveguide with the second waveguide with respect to at least one axis C coincides with at least one stop area (121, 321) of the photonic device resting on a stop surface (221, 421) of a corresponding support structure (223, 423) on the substrate (200, 400), wherein the stop area is a stop in a recess from a surface of the photonic device, wherein the recess is formed by etching of the photonic device, and/or the support structure is formed by etching (211, 212) of the substrate, wherein the etching process (111, 211, 212) is selective with respect to at least one interface between two materials in the photonic device and/or in the substrate, and characterized in that: a) the two materials in the photonic device (100, 300) are chosen from the materials of the core layer, a light emitting layer inside the core layer, an electrical cladding layer inside the core layer, and/or a cladding layer (102, 103, 104), that form part of the first waveguide of the photonic device, and during fabrication, respectively, of the core layer, light emitting layer inside the core layer, the electrical cladding layer inside the core layer, and/or a cladding layer (102, 103, 104), that forms part of the first waveguide of the photonic device, this layer is extended laterally to the location of the recess; or b) the two materials in the substrate (200, 400) are chosen from the materials of the core layer, and/or a cladding layer (202, 203, 204), that form part of the second waveguide which in turn forms part of the substrate, and during fabrication, respectively, of the core layer, and/or a cladding layer (202, 203, 204), that forms part of the second waveguide, this layer is extended laterally to the location of the support structure. a) the two materials in the photonic device (100, 300) are chosen from the materials of the core layer, a light emitting layer inside the core layer, an electrical cladding layer inside the core layer, and/or a cladding layer (102, 103, 104), that form part of the first waveguide of the photonic device, and during fabrication, respectively, of the core layer, light emitting layer inside the core layer, the electrical cladding layer inside the core layer, and/or a cladding layer (102, 103, 104), that forms part of the first waveguide of the photonic device, this layer is extended laterally to the location of the recess; or b) the two materials in the substrate (200, 400) are chosen from the materials of the core layer, and/or a cladding layer (202, 203, 204), that form part of the second waveguide which in turn forms part of the substrate, and during fabrication, respectively, of the core layer, and/or a cladding layer (202, 203, 204), that forms part of the second waveguide, this layer is extended laterally to the location of the support structure.