US 6,387,720 B1 · Waveguide structures integrated with standard CMOS circuitry and methods for making the same

Abstract

A waveguide structure and method of making a waveguide for communicating optical signals is provided. The waveguide structure is made using standard CMOS fabrication operations and is integrated on the same chip having digital CMOS circuitry. An example method of making the waveguide includes forming a contact through a dielectric layer down to a substrate and coating sidewalls of the contact with a first metallization coating. The contact is then filled with a dielectric material. A partial waveguide structure is formed over the first metallization coating and the dielectric material of the contact. The partial waveguide structure is defined by a waveguide dielectric structure and a second metallization coating that is defined over the waveguide dielectric structure. A third metallization coating is then formed to define spacers along sides of the partial waveguide structure, the first metallization coating, the second metallization coating. The third metallization coating is configured to complete the waveguide structure that is filled with the waveguide dielectric structure. Optical signals can then be propagated through the waveguide structure and can be interfaced with other CMOS digital circuitry.

Claims15

Dependent claims

A method for making a waveguide structure implementing CMOS fabrication processes, the method comprising:

providing a substrate having a plurality of active devices fabricated therein and an overlying oxide layer;
defining a contact hole through the oxide layer to define a path down to the substrate;
depositing a first metallization coating over the oxide layer and in the contact hole;
removing the first metallization coating at a base of the contact hole to define the path down to the substrate;
filling the contact hole with a contact hole dielectric material;
forming a waveguide dielectric over the first metallization coating and in contact with the contact hole dielectric material;
forming a second metallization coating over the waveguide dielectric;
patterning the second metallization coating, the waveguide dielectric, and the first metallization coating, the patterning being configured to leave a partial waveguide structure that has the contact hole dielectric material in contact with the waveguide dielectric;
and
forming a third metallization coating over the partial waveguide structure, the third metallization being configured to define metallization spacers that connect the first metallization coating and the second metallization coating and to enclose the waveguide dielectric and define the waveguide structure.

7 more elements

A method of making a waveguide for communicating optical signals, comprising:

forming a contact through a dielectric layer down to a substrate;
coating sidewalls of the contact with a first metallization coating;
filling the contact with a dielectric material;
forming a partial waveguide structure over the first metallization coating and the dielectric material of the contact, the partial waveguide structure being defined by a waveguide dielectric structure and a second metallization coating defined over the waveguide dielectric structure;
and
forming a third metallization coating to define spacers along sides of the partial waveguide structure, the first metallization coating, the second metallization coating and the third metallization coating defining the waveguide that is filled with the waveguide dielectric structure.

3 more elements

Dependencies are inferred from the claim text.

Waveguide structures integrated with standard CMOS circuitry and methods for making the same

Life of this patent

Waveguide structures integrated with standard CMOS circuitry and methods for making the same

Life of this patent

Abstract

Claims15