Evaluating the Impact of STI Recess Profile Control on Advanced FinFET Device Performance

In this paper, a 5 nm FinFET flow was built using the SEMulator3D® virtual fabrication platform. Different STI (shallow trench isolation) recess profiles were investigated using the pattern-dependent etch capabilities of SEMulator3D, including changes in trenching/footing profile, fin height and imbalance fin height. The impact of STI recess profile on device performance was then investigated using a built-in drift-diffusion solver. Our analysis has confirmed that larger footings, lower fin heights and larger imbalance fin heights will generate more severe DIBL problems and lead to higher off-state leakage. STI recess with an optimal trenching profile can increase on-state current and reduce off-state leakage.