Middle-of-line contacts with varying contact area providing reduced contact resistance

Abstract

A method of forming a semiconductor structure includes forming a first portion of a source/drain contact over a source/drain region of a fin-type field-effect transistor (FinFET), the source/drain region being formed over a fin providing a channel region of the FinFET and being adjacent a gate spacer surrounding a gate region of the FinFET. The method also includes forming a first interlayer dielectric (ILD) layer over the first portion of the source/drain contact, the gate spacer and the gate region, and forming a second ILD layer over the first ILD layer. The method further includes forming a second portion of the source/drain contact over the first portion of the source/drain contact in a first opening in the first ILD layer, and forming a third portion of the source/drain contact over the second portion of the source/drain contact in a second opening in the second ILD layer. The second opening is larger than the first opening.