Optical devices and methods of fabricating the same

An optical device comprising:

• a substrate having a waveguide region and a mounting region;
• a planar lightwave circuit (PLC) waveguide including
• a lower-clad layer and an upper-clad layer that each have a waveguide portion disposed on the waveguide region, the lower-clad layer further having a mounting portion disposed on the mounting region, and
• a platform core between the waveguide portions of the lower-clad layer and the upper-clad layer;
• terraces defined by etching the mounting portion of the lower-clad layer;
• platform alignment marks protruding from uppermost surfaces of the terraces so as to extend above the uppermost surfaces of the terraces;
• an optical active chip mounted on the mounting region of the substrate, the optical active chip comprising a chip core therein;
• and
• chip alignment marks disposed on a mounting surface of the optical active chip, the chip alignment marks protruding from the mounting surface so as to extend from the mounting surface of the optical active chip so that the platform alignment marks are disposed between the chip alignment marks, at least one of the chip alignment marks being disposed within the platform alignment marks with a gap therebetween so as to be free of any contact with the platform alignment marks,
• wherein the optical active chip is aligned by interlocking the platform alignment marks and the chip alignment marks, and the optical active chip is mounted on the mounting region.

An optical device comprising:

• a substrate having a waveguide region and a mounting region, the substrate being a silicon substrate;
• a planar lightwave circuit (PLC) waveguide including
• a lower-clad layer and an upper-clad layer that each have a waveguide portion disposed on the waveguide region, the lower-clad layer further having a mounting portion disposed on the mounting region, and
• a platform core between the waveguide portions of the lower-clad layer and the upper-clad layer,
• wherein the lower-clad layer, the platform core, and the upper-clad layer are formed of silica;
• terraces defined by dry etching the mounting portion of the lower-clad layer, each terrace comprising an interlocking part including a trench;
• an optical active chip mounted on the mounting region of the substrate, the optical active chip comprising a chip core therein;
• and
• chip alignment marks disposed on a mounting surface of the optical active chip, the chip alignment marks protruding from the mounting surface so as to extend from the mounting surface of the optical active chip into the trenches so that each trench has a chip alignment mark disposed therein,
• wherein an inner circumference surface of the trenches has a shape corresponding to that of an outer circumference surface of the chip alignment marks, and
• wherein the optical active chip is aligned by interlocking the interlocking parts and the chip alignment marks, and the optical active chip is mounted on the mounting region.