Fan-out co-packaged integrated systems including a photonic integrated circuit
Structures for a co-packaged photonics chip and electronic chip, and associated methods. The structure comprises a layer comprising a molding compound, an electronic chip and a photonics chip affixed in the layer, and a waveguiding structure including a waveguide core adjacent to the photonics chip. The photonics chip includes an optical coupler, the waveguide core includes a portion that overlaps with the optical coupler, and the waveguide core comprises a polymer.
1 . A structure comprising:
a layer comprising a molding compound, the layer including a surface;
an electronic chip affixed in the layer, the electronic chip including a first back-end-of-line stack adjacent to the surface of the layer;
a photonics chip affixed in the layer, the photonics chip including an optical coupler and a second back-end-of-line stack adjacent to the surface of the layer, and the optical coupler including a tapered section;
a redistribution layer disposed on the surface of the layer, the redistribution layer including a plurality of interconnects configured to couple the first back-end-of-line stack in electrical communication with the second back-end-of-line stack; and
a waveguiding structure including a waveguide core adjacent to the photonics chip, the waveguide core including a tapered section that overlaps with the tapered section of the optical coupler, and the waveguide core comprising a first polymer,
wherein the optical coupler of the photonics chip and the tapered section of the waveguide core are disposed adjacent to the surface of the layer.
2 . The structure of claim 1 wherein the waveguiding structure includes a first cladding layer and a second cladding layer, and the waveguide core includes a portion that is surrounded by the first cladding layer and the second cladding layer.
3 . The structure of claim 2 wherein the first cladding layer is affixed in the layer below the surface, and the second cladding layer is disposed above the surface of the layer.
4 . The structure of claim 2 wherein the first cladding layer comprises a second polymer with a different refractive index than the first polymer.
5 . The structure of claim 2 wherein the second cladding layer comprises a second polymer with a different refractive index than the first polymer.
6 . A method comprising:
forming a package assembly including an electronic chip and a photonics chip affixed in a layer comprising a molding compound, wherein the layer includes a surface, the electronic chip includes a first back-end-of-line stack adjacent to the surface of the layer, the photonics chip includes an optical coupler and a second back-end-of-line stack adjacent to the surface of the layer, and the optical coupler of the photonics chip is disposed adjacent to the surface of the layer;
forming a redistribution layer disposed on the surface of the layer, wherein the redistribution layer includes a plurality of interconnects configured to couple the first back-end-of-line stack in electrical communication with the second back-end-of-line stack; and
forming a waveguide core of a waveguiding structure adjacent to the photonics chip, wherein the waveguide core includes a first portion that overlaps with the optical coupler, the first portion of the waveguide core is disposed adjacent to the surface of the layer, and the waveguide core comprises a polymer,
wherein forming the package assembly including the electronic chip and the photonics chip affixed in the layer comprising the molding compound comprises:
attaching the electronic chip and the photonics chip in a removable manner to a carrier substrate; and
forming the layer over the electronic chip and the photonics chip to form the package assembly; and
wherein forming the waveguide core of the waveguiding structure adjacent to the optical coupler comprises:
removing the package assembly from the carrier substrate; and
forming the waveguide core after the package assembly is removed from the carrier substrate.
7 . The method of claim 6 wherein forming the package assembly including the electronic chip and the photonics chip affixed in the layer comprising the molding compound comprises:
forming a first cladding layer of the waveguiding structure that is affixed in the layer.
8 . The method of claim 7 wherein the waveguide core includes a second portion, and the second portion of the waveguide core is formed on the first cladding layer.
9 . The method of claim 8 further comprising:
forming a second cladding layer on the first cladding layer and the second portion of the waveguide core,
wherein the second portion of the waveguide core is surrounded by the first cladding layer and the second cladding layer.
10 . The structure of claim 1 wherein the redistribution layer is disposed directly on the surface of the layer.
11 . The method of claim 6 wherein the redistribution layer is disposed directly on the surface of the layer.
12 . The structure of claim 2 wherein the first cladding layer comprises a second polymer having a lower refractive index than the first polymer.
13 . The structure of claim 2 wherein the second cladding layer comprises a second polymer having a lower refractive index than the first polymer.
14 . The structure of claim 1 wherein the optical coupler comprises silicon or silicon nitride.