Methods of forming silicide layers on source/drain regions of MOS transistors

摘要

Methods of forming MOS transistors include forming lightly and heavily doped source/drain regions adjacent to one another in a substrate and a gate electrode with a sidewall spacer thereon. A salicide process is performed on a surface of the heavily doped source/drain region to provide a first suicide layer self-aligned to the sidewall spacer. At least a portion of the sidewall spacer is removed to expose a portion of the lightly doped source/drain region adjacent to the first silicide layer. A salicide process in performed on the exposed portion of the lightly doped source/drain region to provide a second silicide layer adjacent to the first suicide layer. Related devices are also disclosed.