In this paper, the optimum shallow trench isolation, together with Ni silicide technology, is introduced to implement the strained-Si negative-metal-oxide semiconductor field-effect transistors (nMOSFETs) and shows well-behaved characteristics using the 0.18 mu m complementary metal-oxide semiconductor process. It is found that the strained-Si nMOSFET provides a strong enhancement (up to 75%) in long-channel mobility when compared to a Si control device. The increased mobility behavior is translated into a 70% higher driving current for the large-area devices (W x L = 10 x 10 mu m) and a 51% higher driving current for device pattern down to W x L = 0.3 x 0.18 mu m. Significant pattern effects for strained-Si devices with NiSi is observed, which is the result of the formation of nonuniform Ni silicide at the source/drain region and is responsible for the increased source/drain resistance and off-state leakage. (C) 2008 The Electrochemical Society.