Semiconductor device with reduced trap defect and method of forming the same

Abstract

A method of manufacturing a semiconductor device includes: providing a substrate comprising a surface; forming fins on the substrate; depositing a dummy gate electrode over the fins; forming a gate spacer surrounding the dummy gate electrode; forming lightly-doped source/drain (LDD) regions in the substrate on two sides of the gate spacer; performing a first treatment at a first temperature to repair defects in at least one of the dummy gate electrode, the gate spacer and the LDD region; forming source/drain regions in the respective LDD regions; removing the dummy gate electrode to form a replacement gate; depositing an inter-layer dielectric (ILD) layer over the replacement gate and the source/drain regions; and subsequent to the forming of the replacement gate, performing a second treatment at a second temperature, lower than the first temperature, to repair defects of the semiconductor device.