Position controlled waveguides and methods of manufacturing the same

A method of manufacturing a waveguide, the method comprising:

• etching a cavity into a first surface of a substrate, the cavity defined by first and second sidewalls and a second surface, the second surface recessed relative to the first surface;
• depositing a first material onto the second surface of the substrate, the first material having a first index of refraction;
• depositing a second material onto the first material, the second material having a second index of refraction that is higher than the first index of refraction, the first and second materials to completely cover the second surface of the substrate across a distance between the first and second sidewalls of the cavity;
• etching the second material between the first sidewall and the second sidewall to separate a first portion of the second material from a second portion of the second material;
• and
• depositing a third material within the cavity, the first and second materials to be enclosed by the substrate and the third material, the third material having an index of refraction that matches the first index of refraction.

A method of manufacturing a waveguide, the method comprising:

• etching a cavity into a first surface of a substrate, the cavity defined by first and second sidewalls and a second surface, the second surface recessed relative to the first surface, the substrate between a first optical component and a second optical component, the first optical component including an optical signal emitter, and the second optical component including an optical signal receiver;
• depositing a first material onto the second surface of the substrate, the first material having a first index of refraction;
• measuring a depth of the cavity to the first material during deposition of the first material;
• modifying deposition of the first material based on the measured depth of the cavity to the first material relative to a position of the optical signal emitter and the optical signal receiver to facilitate alignment of a second material with the optical signal emitter and the optical signal receiver;
• depositing the second material onto the first material, the second material having a second index of refraction that is higher than the first index of refraction;
• and
• depositing a third material within the cavity, the first and second materials to be enclosed by the substrate and the third material, the third material having an index of refraction that matches the first index of refraction.

A method of manufacturing a waveguide, the method comprising:

• etching a cavity into a first surface of a substrate, the cavity defined by first and second sidewalls and a second surface, the second surface recessed relative to the first surface;
• depositing a first material onto the second surface of the substrate, the first material having a first index of refraction;
• depositing a second material onto the first material, the second material having a second index of refraction that is higher than the first index of refraction, the first and second materials to completely cover the second surface across a distance between the first and second sidewalls;
• etching the second material to create a first gap between the first sidewall and the second material and to create a second gap between the second sidewall and the second material;
• and
• depositing a third material within the cavity, the third material to fill the first and second gaps, the first and second materials to be enclosed by the substrate and the third material, the third material having an index of refraction that matches the first index of refraction.

A method of manufacturing a waveguide, the method comprising:

• etching a cavity into a first surface of a substrate, the cavity defined by first and second sidewalls and a second surface, the second surface recessed relative to the first surface;
• depositing a first material onto the second surface of the substrate, the first material having a first index of refraction;
• depositing a release layer onto the first surface of the substrate, the release layer to overhang portions of the cavity adjacent the first sidewall and the second sidewall;
• depositing a second material onto the first material, the second material having a second index of refraction that is higher than the first index of refraction, the overhang of the release layer to block the second material from being deposited directly adjacent the first and second sidewalls to create a first gap between the first sidewall and the second material and to create a second gap between the second sidewall and the second material;
• and
• depositing a third material within the cavity, the first and second materials to be enclosed by the substrate and the third material, the third material having an index of refraction that matches the first index of refraction, the third material to fill the first and second gaps.

A method of manufacturing a waveguide, the method comprising:

• etching a cavity into a first surface of a substrate, the cavity defined by first and second sidewalls and a second surface, the second surface recessed relative to the first surface;
• depositing a first material onto the second surface of the substrate, the first material having a first index of refraction;
• depositing multiple layers of buffer material onto the second surface, the multiple layers of buffer material including the first material;
• depositing a second material onto the multiple layers of buffer material, the second material having a second index of refraction that is higher than the first index of refraction, each of the multiple layers of buffer material having a different index of refraction to define a graded refraction interface adjacent the second material;
• and
• depositing a third material within the cavity, the first and second materials to be enclosed by the substrate and the third material, the third material having an index of refraction that matches the first index of refraction.

An apparatus comprising:

• a substrate including a trench in a first surface of the substrate, the trench defined by a first sidewall, a second sidewall facing the first sidewall, and a trench bottom that extends between the first and second sidewalls, a depth of the trench corresponding to a first distance from the first surface to the trench bottom;
• a first waveguide within the trench, a second distance between the trench bottom and the first waveguide being less than the first distance;
• a second waveguide within the trench, the second waveguide spaced apart from the first waveguide;
• and
• a filler material to fill a space between the first and second waveguides, the filler material to extend a full distance from the first waveguide to the second waveguide.