Electro-optical phase modulator
AssigneeSTMicroelectronics (Crolles 2) SAS
InventorStephane MONFRAY
Life of this patent
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Abstract
An electro-optical phase modulator includes a waveguide made from a stack of strips. The stack includes a first strip made of a doped semiconductor material of a first conductivity type, a second strip made of a conductive material or of a doped semiconductor material of a second conductivity type, and a third strip made of a doped semiconductor material of the first conductivity type. The second strip is separated from the first strip by a first interface layer made of a dielectric material, and the third strip is separated from the second strip by a second interface layer made of a dielectric material.
Claims13
A method, comprising:
- etching a semiconductor layer of a silicon-on-insulator (SOI) substrate to form a first strip portion of a waveguide comprising a first region having a first thickness and a second region having a second thickness that is smaller than the first thickness;
- covering the first strip portion with an insulating material;
- forming an opening in the insulating material that exposes an upper surface of the first region, with the insulating material remaining at a bottom of the opening sufficient to cover an upper surface of second region;
- covering the exposed upper surface of the first region with a first insulating layer;
- forming a second strip portion of the waveguide on the first insulating layer and on the insulating material at the bottom of the opening;
- covering an upper surface of the second strip portion with a second insulating layer;
- and
- forming a third strip portion of the waveguide on the second insulating layer and on the insulating material at the bottom of the opening.
Dependencies are inferred from the claim text.