Design and Performance Analysis of FinFET-Based Digital Circuits

Abstract

The continual downscaling of transistor dimensions in advanced semiconductor technologies has accentuated the limitations of conventional planar CMOS devices, notably the pronounced short-channel effects: threshold voltage roll-off and elevated leakage currents observed at deep nanometer regimes. To address these constraints, this study presents a comprehensive Design and Performance Analysis of FinFET-Based Digital Circuits, focusing on Inverter, NAND and NOR gates implemented using predictive SPICE models. FinFET technology, with its tri-gate structure and superior electrostatic control, is evaluated alongside conventional CMOS and emerging CNFET architectures to assess improvements in speed, leakage, and energy efficiency. Device-level simulations were conducted in Silvaco TCAD to validate a 20 nm FinFET structure, while circuit-level analyses employed Cadence Virtuoso using PTM 32 nm CMOS, PTM 7 nm FinFET, and Stanford–MIT VS-CNFET models. Key performance metrics propagation delay, static leakage power, average power, and power-delay product (PDP) were extracted for cross-technology comparison: results showing FinFET circuits to achieve over 95% reduction in static leakage and nearly 90% improvement in PDP relative to CMOS, owing to enhanced gate control and reduced parasitics. CNFET circuits exhibit the best theoretical performance with ultra-low leakage and minimal PDP, attributed to quasi ballistic carrier transport. To further optimize power consumption, two circuit-level leakage control schemes, LECTOR and INDEP, were implemented. The LECTOR–FinFET configuration achieved consistent leakage suppression with minimal delay penalty, whereas INDEP–FinFET offered more aggressive leakage reduction- up to 92%- at the cost of higher propagation delay and PDP. Overall, FinFET integrated with LECTOR optimization demonstrates the most practical and energy-efficient architecture for nanoscale digital circuit design, whereas CNFET remains a promising candidate for future ultra-low-power VLSI systems pending fabrication maturity.