The researchers first placed an ultrathin epitaxial aluminium layer directly on the MoS2.They then oxidised the aluminium to create an aluminium oxide layer about 0.42 nanometres thick. They placed the ultrathin epitaxial aluminium layer on monolayer MoS2 and oxidised it to produce the 0.42-nanometre aluminium oxide layer. The high-κ hafnium oxide was then added on top.The team built short-channel top-gate transistors using CVD-grown monolayer MoS2. Hysteresis refers to unwanted differences in a transistor's electrical response depending on its previous operating condition.The transistors reached a maximum transconductance of 0.45 mS μm-1, with channel lengths of about 100 nanometres. Using CVD-grown monolayer MoS2 also brings the work closer to materials and processes that could eventually be considered for wafer-scale manufacturing.