Methods for forming contacts for dual stress liner CMOS semiconductor devices

Semiconductor fabrication methods to forma of via contacts in DSL (dual stress liner) semiconductor devices are provided, in which improved etching process flows are implemented to enable etching of via contact openings through overlapped and non-overlapped regions of the dual stress liner structure to expose underlying salicided contacts and other device contacts, while mitigating or eliminating defect mechanisms such as over etching of contact regions underlying non-overlapped regions of the DSL.