Optical dielectric planar waveguide process

A method comprising

• depositing multiple layers of films on a substrate,
• wherein the multiple layers of films comprises a stack of silicon oxynitride films;
• and
• patterning the multiple layers of films to form a waveguide with a core of the waveguide comprising silicon oxynitride,
• wherein at least a silicon oxynitride film in the stack of silicon oxynitride films is deposited using a plasma enhanced chemical vapor deposition (PECVD) process, and
• wherein process gases in the PECVD process comprise an amount of hydrogen configured to form the at least a silicon oxynitride film having a stress level less than 25 MPa in magnitude or configured to form the at least a silicon oxynitride film using process temperatures less than 500 C to prevent damages to the substrate.

A method comprising

• depositing multiple layers of films on a substrate,
• wherein the multiple layers of films comprises a stack of silicon oxynitride films;
• and
• patterning the multiple layers of films to form a waveguide with a core of the waveguide comprising silicon oxynitride,
• wherein at least a silicon oxynitride film in the stack of silicon oxynitride films is deposited using a plasma enhanced chemical vapor deposition (PECVD) process, and
• wherein process gases in the PECVD process comprise an amount of hydrogen configured to form the at least a silicon oxynitride film, as-deposited, having a level of optical loss of less than 1 dB/cm.