Optical connection structure and optical module

An optical connection structure comprising:

• a first silicon photonic chip having a first lateral surface;
• a second silicon photonic chip having a second lateral surface and disposed such that the second lateral surface faces the first lateral surface;
• an optical waveguide disposed astride a gap between the first silicon photonic chip and the second silicon photonic chip;
• and
• a support substrate,
• wherein the first silicon photonic chip includes:
• a first silicon substrate;
• and
• a first silicon waveguide disposed over an upper surface of the first silicon substrate, the second silicon photonic chip includes:
• a second silicon substrate;
• and
• a second silicon waveguide disposed over an upper surface of the second silicon substrate, and
• the optical waveguide includes:
• a first cladding filling a space between the first lateral surface and the second lateral surface;
• a core disposed on the first cladding and covering one end of the first silicon waveguide and one end of the second silicon waveguide, the core optically connecting the first silicon waveguide and the second silicon waveguide;
• and
• a second cladding covering the core,
• wherein a lower surface of the first silicon substrate is attached to an upper surface of the support substrate via a first adhesive layer, and a lower surface of the second silicon substrate is attached to the upper surface of the support substrate via a second adhesive layer, and
• wherein the support substrate and the first silicon photonic chip are not electrically connected to each other, and the support substrate and the second silicon photonic chip are not electrically connected to each other.