Scaling aligned carbon nanotube transistors to a sub-10 nm node

Aligned semiconducting carbon nanotubes are a potential alternative to silicon in the creation of scaled field-effect transistors (FETs) due to their easy miniaturization and high energy efficiency. However, it remains unclear whether aligned nanotube transistors can be fabricated at the same dimensions as low-node silicon technology and maintaining high performance. Here we report aligned carbon nanotube FETs that can be scaled to a size corresponding to the 10 nm silicon technology node. We first fabricate nanotube FETs with a contacted gate pitch of 175 nm (achieved by scaling the gate length and contact length to 85 nm and 80 nm, respectively) that exhibit an on current of 2.24 mA μm–1 and peak transconductance of 1.64 mS μm–1; this is superior to 45 nm silicon technology node transistors in terms of size and electronic performance. Six nanotube FETs are used to create a static random-access memory cell with an area of 0.976 μm2, which is comparable with the 90 nm silicon technology node. A full-contact structure is then introduced between the metal and nanotubes to achieve a low contact resistance of 90 Ω μm and reduce the dependence on the contact length. This is used to create nanotube FETs with a contacted gate pitch of 55 nm—corresponding to the 10 nm node—with carrier mobility and Fermi velocity higher than the 10 nm silicon metal–oxide–semiconductor transistors. Aligned carbon nanotubes can be used to create six-transistor static random-access memory cells with an area of less than 1 μm2 and performance superior to cells made using 90-nm-node silicon transistors, as well as field-effect transistors with scaled contacted gate pitch comparable with the 10 nm silicon technology node.