Systematic understanding of channel-size dependence of low-frequency noise in 10nm-diameter tri-gate nanowire MOSFETs

We systematically study the channel size dependence of 1/f noise and RTN amplitude in nanowire transistors (NW Tr.) by measuring a large number of samples with various parameters such as NW width (W_NW), height (H_NW), and number (N_NW). For a wide range of L_g, W_NW and H_NW, the universal line appears in the noise (S_Id/I_d²) - 1/(L_gW_eff) plot explained by conventional carrier number fluctuations. But, the noise of narrowest (10nm-diameter) NW Tr. rapidly increases with 1/W_NW due to bottleneck effects and the noise of short-L_g Tr. (down to 15nm) saturates due to the reduction of channel area and a number of traps. Channel doping causes bottleneck effects and noise increase in the same way as NW thinning. The reduction of both trap density and channel area affected by a single trap is essential to reduce the noise in NW Tr.