SELF-ALIGNED SOURCE/DRAIN CONTACTS

摘要

A semiconductor substrate includes lower source/drain (S/D) regions. A replacement metal gate (RMG) structure is arranged upon the semiconductor substrate between the lower S/D regions. Raised S/D regions are arranged upon the lower S/D regions adjacent to the RMG structure, respectively. The raised S/D regions may be recessed to form contact trenches. First self-aligned contacts are located upon the raised S/D regions within a first active area and second self-aligned contacts are located upon the recessed raised S/D regions in the second active area. The first and second self-aligned contacts allows for independent reduction of source drain contact resistances. The first self-aligned contacts may be MIS contacts or metal silicide contacts and the second self-aligned contacts may be metal-silicide contacts.

主权项

1. A semiconductor structure fabrication method comprising:
forming first lower source/drain (S/D) regions within or upon a first active area of a semiconductor substrate; forming second lower S/D regions within or upon a second active area of the semiconductor substrate; forming a first replacement metal gate (RMG) structure upon the semiconductor substrate between the first lower S/D regions; forming a second RMG structure upon the semiconductor substrate between the second lower S/D regions; forming first raised S/D regions upon the first lower S/D regions adjacent to the first RMG structure; forming second raised S/D regions upon the second lower S/D regions adjacent to the second RMG structure; recessing the first raised S/D regions forming first area contact trenches; capping the first area contact trenches; recessing the second raised S/D regions forming second area contact trenches; forming second self-aligned contacts upon the second recessed raised S/D regions within the second area contact trenches; capping the second self-aligned contacts, and; forming first self-aligned contacts upon the first recessed raised S/D regions.