Effect of the Single- and Dual-k Spacers on a Negative-capacitance Fin Field-effect Transistor

The influence of single- and double-k spacer structures on the performance of a negative-capacitance fin field-effect transistor (NC-FinFET) is investigated in this work. Sentaurus technology computer-aided design simulation reveals that due to the negative- capacitance effect, the difference between the single-k and double-k spacers on the FinFET performance is reflected in the drain-induced barrier lowing (DIBL), subthreshold swing (SS), and switching current ratio. The double-k spacer shows stronger gate controllability and better capacitance matching than the single-k spacer. Thus, the double-k spacer is more beneficial to improving intrinsic delay than the single-k spacer. In addition, by adjusting the combination of spacer materials and structures, the NC-FinFET can achieve a switching current ratio of up to 10(8), an SS of 57 mV/dec, and a DIBL of - 47 mV/V. This work provides spacer optimizations via selecting appropriate structure and materials for NC-FinFET.