Patent ID: 8548287

Claim:
A multi-chip module (MCM), comprising: a first substrate having a first surface, wherein the first substrate includes: a first optical waveguide disposed on the first surface; and a first optical coupler, optically coupled to the first optical waveguide, having a first vertical facet, wherein the first optical coupler has a first optical mode that is different than a second optical mode associated with the first optical waveguide; and a second substrate having a second surface facing the first surface of the first substrate, wherein the second substrate includes: a second optical waveguide disposed on the second surface; and a second optical coupler, optically coupled to the second optical waveguide, having a second vertical facet, wherein the second optical coupler has a third optical mode that is different than a fourth optical mode associated with the second optical waveguide; wherein the second vertical facet is horizontally displaced relative to and faces the first vertical facet, thereby facilitating direct optical coupling of an optical signal from the first vertical facet to the second vertical facet.