Semiconductor structure and method for fabricating same

Abstract

Embodiments relate to a semiconductor structure and a method for fabricating the same. The semiconductor structure includes: a base substrate including a trench, where the trench includes a gate structure whose top surface is lower than a top surface of the trench; first etch stop layers, where the first etch stop layers cover the top surface of the gate structure, part of a side wall of the trench, and an upper surface of the base substrate; an enclosed isolation structure positioned between the first etch stop layers in the trench, where the enclosed isolation structure at least plugs an opening of the trench; and an air gap positioned between the first etch stop layer and the enclosed isolation structure, where the air gap at least includes a transverse portion, and a bottom of the enclosed isolation structure is positioned on the transverse portion.

Dependencies are inferred from the claim text.