SEMICONDUCTOR ISOLATION STRUCTURES AND METHODS OF FORMING SAME

The present disclosure relates to isolation structures for semiconductor devices and, more particularly, to dual trench isolation structures having a deep trench and a shallow trench for electrically isolating integrated circuit (IC) components formed on a semiconductor substrate. The semiconductor isolation structure of the present disclosure includes a semiconductor substrate, a shallow trench isolation (STI) disposed over the semiconductor substrate, a deep trench isolation (DTI) with sidewalls extending from a bottom surface of the STI and terminating in the semiconductor substrate, a multilayer dielectric lining disposed on the sidewalls of the DTI, the multilayer dielectric lining including an etch stop layer positioned between inner and outer dielectric liners, and a filler material disposed within the DTI.