Negative drain-induced barrier lowering and negative differential resistance effects in negative-capacitance transistors

In this study, the negative drain-induced barrier lowering (DIBL) and negative differential resistance (NDR) effects are investigated in detail in negative-capacitance field-effect transistors (NCFETs) with a fully depleted silicon-on-insulator structure. We show that the negative DIBL and NDR effects are caused by a decrease in the internal gate voltage, which is closely related to the matching between the ferroelectric capacitance and the total gate capacitance of the underlying FET. Further, we define the remnant-polarization-to-coercive-field ratio (R-PE), which can be directly used as a parameter to quantify the DIBL effect and describe the sign of the NDR effect. DIBL tends to be consistent with the same R-PE, despite exhibiting different current intensities in the strong inversion region. With regard to different RPE, the DIBL effect decreases but the NDR effect increases as R-PE decreases. Our work may provide further insight for NCFET designers to adjust capacitance matching to optimize the DIBL and NDR effects.

Automated summary

This study investigates the negative DIBL and NDR effects in NCFETs with a fully depleted silicon-on-insulator structure, showing that these effects are closely related to the decrease in internal gate voltage. The newly defined parameter R-PE can quantify the DIBL effect and describe the NDR effect. Our findings suggest that DIBL tends to be consistent with the same R-PE, while the DIBL effect decreases and the NDR effect increases with decreasing R-PE.