MoS2 negative capacitance FETs with CMOS-compatible hafnium zirconium oxide
© 2017 IEEE. The attractiveness of negative capacitance field-effect transistors (NC-FETs) stems from their ability to enable a subthreshold swing (SS) below the 60 mV/decade thermal limit at room temperature - a direct effect of the step-up voltage amplifier behavior of the ferroelectric . This effect has been shown to yield sub-60 mV/dec SS in several Si-based NC-FETs [2-4]; however, as Si-based devices become increasingly difficult to scale, it is pertinent to explore alternative materials for NC-FETs that offer scalability in voltage as well as size . One promising alternative channel material is the 2D transition metal dichalcogenide (TMD, such as MoS2), which offer sub-nm thinness and a more stable channel capacitance that, when coupled with the NC-effect, could produce steep switching over a broad range of current. To date, the only demonstration of an NC-FET with a 2D channel used a polymeric ferroelectric, resulting in a lack of stability and CMOS-compatibility despite superb low-voltage switching . In this work, we demonstrate 2D NC-FETs using MoS2 with CMOS-compatible hafnium zirconium oxide (HfZrO2 or HZO) as the ferroelectric to achieve repeatable and sustained sub-60 mV/dec switching.
McGuire, FA; Lin, YC; Rayner, B; Franklin, AD
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International Standard Book Number 13 (ISBN-13)
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