Optical integrated circuit

A method for fabricating an optical integrated circuit, comprising the steps of:

• providing a substrate with one or more optical waveguides arranged in the substrate;
• forming, for example by means of etching, at least one open cavity in the substrate, thereby forming at least one set of optical waveguides for each open cavity, each set comprising a first optical waveguide and a second optical waveguide, wherein the first optical waveguide and the second optical waveguide of a set are each arranged in the substrate and each comprise a first end facet ending in the open cavity of that set, and
• forming in the open cavity of a set and for each set a first collimating element at or near the first end facet of the first optical waveguide of that set and a second collimating element at the first end facet of the second optical waveguide of that set,
• wherein forming, for example by means of etching, each open cavity comprises etching through at least one optical waveguide interrupting at least that optical waveguide in different segments thereby forming the at least one set of optical waveguides for each open cavity, and
• wherein forming the collimating elements comprises filling the open cavity of a set with a first photo-sensitive material, locally polymerizing said first photo-sensitive material and subsequently curing the polymerized first photo-sensitive material to obtain the first and second collimating elements having a first refractive index, and
• curing but not polymerizing material arranged in the cavity, to obtain material having a second refractive index different from the first refractive index and acting as a mechanical support for supporting the first and second collimating elements;
• further comprising providing a binding material in a recess formed to secure an optical component between the first and second collimating elements.