LAB-to-FAB Transition of 2D FETs: Available Strategies and Future Trends.

The last decade has seen dramatic progress in research on FETs with 2D channels. Starting from the single devices fabricated using exfoliated flakes in the early 2010s, by the early 2020s, 2D FETs being trialed for mass production and vertical stacking of 2D channels made by leading semiconductor companies. However, the industry is focused solely on transition metal dichalcogenide (TMD) channels coupled with conventional 3D oxide insulators such as AlO and HfO.

Improving stability in two-dimensional transistors with amorphous gate oxides by Fermi-level tuning.

Electronic devices based on two-dimensional semiconductors suffer from limited electrical stability because charge carriers originating from the semiconductors interact with defects in the surrounding insulators. In field-effect transistors, the resulting trapped charges can lead to large hysteresis and device drifts, particularly when common amorphous gate oxides (such as silicon or hafnium dioxide) are used, hindering stable circuit operation. Here, we show that device stability in graphene-based field-effect transistors with amorphous gate oxides can be improved by Fermi-level tuning.

Perspective of 2D Integrated Electronic Circuits: Scientific Pipe Dream or Disruptive Technology?

Within the last decade, considerable efforts have been devoted to fabricating transistors utilizing 2D semiconductors. Also, small circuits consisting of a few transistors have been demonstrated, including inverters, ring oscillators, and static random access memory cells. However, for industrial applications, both time-zero and time-dependent variability in the performance of the transistors appear critical.

Dielectric Properties of Ultrathin CaF Ionic Crystals.

Mechanically exfoliated 2D hexagonal boron nitride (h-BN) is currently the preferred dielectric material to interact with graphene and 2D transition metal dichalcogenides in nanoelectronic devices, as they form a clean van der Waals interface. However, h-BN has a low dielectric constant (≈3.9), which in ultrascaled devices results in high leakage current and premature dielectric breakdown.

Insulators for 2D nanoelectronics: the gap to bridge.

Nanoelectronic devices based on 2D materials are far from delivering their full theoretical performance potential due to the lack of scalable insulators. Amorphous oxides that work well in silicon technology have ill-defined interfaces with 2D materials and numerous defects, while 2D hexagonal boron nitride does not meet required dielectric specifications. The list of suitable alternative insulators is currently very limited.

Characterization of Single Defects in Ultrascaled MoS Field-Effect Transistors.

MoS has received a lot of attention lately as a semiconducting channel material for electronic devices, in part due to its large band gap as compared to that of other 2D materials. Yet, the performance and reliability of these devices are still severely limited by defects which act as traps for charge carriers, causing severely reduced mobilities, hysteresis, and long-term drift. Despite their importance, these defects are only poorly understood.

Long-Term Stability and Reliability of Black Phosphorus Field-Effect Transistors.

Black phosphorus has been recently suggested as a very promising material for use in 2D field-effect transistors. However, due to its poor stability under ambient conditions, this material has not yet received as much attention as for instance MoS. We show that the recently demonstrated AlO encapsulation leads to highly stable devices.