US 12,282,192 B2
Method for fabricating a photonic chip
Leopold Virot, Grenoble (FR); Jean-Michel Hartmann, Grenoble (FR); Karim Hassan, Grenoble (FR); Bertrand Szelag, Grenoble (FR); and Quentin Wilmart, Grenoble (FR)
Assigned to Commissariat à l'Energie Atomique et aux Energies Alternatives, Paris (FR)
Filed by Commissariat à l'Energie Atomique et aux Energies Alternatives, Paris (FR)
Filed on Dec. 5, 2022, as Appl. No. 18/061,523.
Claims priority of application No. 21 13761 (FR), filed on Dec. 17, 2021.
Prior Publication US 2023/0194789 A1, Jun. 22, 2023
Int. Cl. G02B 6/132 (2006.01); G02B 6/12 (2006.01); G02B 6/13 (2006.01); G02B 6/136 (2006.01); H01L 21/02 (2006.01)
CPC G02B 6/132 (2013.01) [G02B 6/131 (2013.01); G02B 6/136 (2013.01); H01L 21/02532 (2013.01); H01L 21/0254 (2013.01); H01L 21/02645 (2013.01); G02B 2006/12061 (2013.01); G02B 2006/12169 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for fabricating a photonic chip comprising a first waveguide made of stoichiometric silicon nitride, a second waveguide made of crystalline semiconductor material and at least one active component optically coupled to the first waveguide via the second waveguide, said method comprising:
providing a substrate made of monocrystalline silicon on which is deposited a layer made of dielectric material, said substrate extending primarily in a plane called “plane of the substrate”, then
vapour depositing, on the layer made of dielectric material, a layer of stoichiometric silicon nitride followed by an annealing at a temperature of between 1000° C. and 1400° C., then
producing the first waveguide in said deposited and annealed layer of stoichiometric silicon nitride, then
encapsulating the first waveguide in a dielectric material to obtain an encapsulation layer wherein the first waveguide is encapsulated, said encapsulation layer having a top face on the side opposite the substrate, then
creating a layer made of crystalline semiconductor material directly on the top face of the encapsulation layer, then
producing the second waveguide in said layer made of crystalline semiconductor material, said second waveguide being optically coupled to the first waveguide by an evanescent coupling, then
producing the active optical component, said active optical component being connected optically to the first waveguide via the second waveguide, then
producing electrical ports to electrically connect the active optical component to an electrical power source,
wherein the creating of the layer made of crystalline semiconductor material comprises the following operations:
a) forming an aperture which passes through the encapsulation layer and emerges in or on the substrate, then
b) depositing by epitaxial growth of a crystalline seeding material inside the aperture until said crystalline seeding material reaches the top face and forms a crystalline seed on said top face, said crystalline seeding material having mesh parameters that are identical, to within plus or minus 5%, to those of the crystalline semiconductor material, then
c) a lateral epitaxy, of the same crystalline semiconductor material as that wherein the second waveguide is produced, from the crystalline seed formed to form the layer made of crystalline semiconductor material wherein the second waveguide is then produced.