Reduced RTN Amplitude and Single Trap induced Variation for Ferroelectric FinFET by Substrate Doping Optimization

Abstract

In this paper, we investigate the impacts of single trap induced Random Telegraph Noise (RTN) on Ferroelectric FinFET (FE-FinFET) with P-type and N-type substrates respectively, compared to FinFET. The trap position dependent RTN amplitude $\left(\Delta \mathbf{I}_{\mathrm{d} /} / \mathbf{I}_{\mathrm{ds}}\right)$ along the channel length and fin height directions are examined. For FE-FinFET and FinFET at $\mathbf{V}_{\mathbf{g s}}$= 0V, N-type substrate with smaller work function lowers the channel conduction band energy near the bottom of fin along the fin height direction. Therefore, the maximum electron current density occurs at the bottom of fin which becomes the most critical position introducing worst RTN amplitude for N-type substrate. However, for FE-FinFET and FinFET with P-type substrate, the worst RTN amplitude occurs at 0.5 fin height position. Therefore, along the fin height direction, the worst RTN amplitude occurs at different position for FE-FinFET/FinFET with N-type and P-type substrates respectively. Our results show that FE-FinFET exhibits smaller RTN amplitude than FinFET due to its smaller trap induced threshold voltage shift $\left(\Delta \mathbf{V}_{\mathrm{T}}\right)$. Besides, for both FE-FinFET and FinFET, N-type substrate shows smaller RTN amplitude and RTN induced $\Delta \mathbf{V}_{\mathbf{T}}$ variations than P-type substrate. In other words, RTN induced variations can be suppressed by substrate doping optimization for FE-FinFET and FinFET.