Low-Frequency Noise Analysis and Modeling in Vertical Tunnel FETs With Ge Source

This paper presents the low-frequency noise (LFN) behavior of vertical tunnel FETs (TFETs). The experimental input characteristics with different source compositions (Si and Ge) and different HfO
₂
thicknesses in the gate-stack (2 and 3 nm) are presented. A brief analog parameters analysis, including the transconductance, output conductance, and intrinsic voltage gain behavior under different bias conditions, shows that TFETs are promising for analog applications. For the LFN study, the standard number fluctuations model for MOSFETs was used in order to verify and compare the TFETs noise behavior, exploring the influence of different conduction mechanisms in each bias region. In the proposed model, the effective channel length (L
_eff
) is replaced by the tunneling length, resulting in good agreement between the experimental data and the model. The temperature influence on the TFET noise behavior is also investigated.