US Patent 9837491 Stacked carbon nanotube multiple threshold device

A device structure including a gate structure containing a first layer of carbon nanotubes and a second layer of carbon nanotubes. The first and the second layers are stacked vertically. The first and the second layers have carbon nanotubes which have substantially homogeneous electric characteristics within each layer. The carbon nanotubes in the first layer have different electric characteristics than the carbon nanotubes in the second layer, so that the device structure exhibits a multiple threshold behavior when coupled to a voltage source. The disclosure also includes a method for fabricating a multithreshold device structure.