Semiconductor photonics device and methods of formation

Abstract

A semiconductor photonics device includes an optical modulator structure and a modulator heater structure in one or more dielectric layers of the semiconductor photonics device. An isolation trench is included around the modulator heater structure to reduce the likelihood of damage to the dielectric layer(s) that might otherwise be caused by thermal stress. The isolation trench may include an air gap through the dielectric layer(s), and the air gap surrounds the modulator heater structure in a top-down view of the semiconductor photonics device. The isolation trench reduces the amount of heat absorbed in the dielectric layer(s) in that the isolation trench thermally isolates the modulator heater structure from the dielectric layer(s). This reduces the likelihood of cracking, delamination, and/or another type of damage to the dielectric layer(s) that might otherwise be caused by thermal stress to the dielectric layer(s).