Trench isolation with conductive structures

Abstract

The present disclosure describes a semiconductor device having metal boundary trench isolation with electrically conductive intermediate structures acting as a metal diffusion barrier. The semiconductor structure includes a first fin structure and a second fin structure on a substrate, an insulating layer between the first and second fin structures, a gate dielectric layer on the insulating layer and the first and second fin structures, and a first work function stack and a second work function stack on the gate dielectric layer. The first work function stack is over the first fin structure and a first portion of the insulating layer, and the second work function stack is over the second fin structure and a second portion of the insulating layer adjacent to the first portion. The semiconductor structure further includes a conductive intermediate structure on the gate dielectric layer and between the first and second work function stacks.