Nanometer heterostructure and nanometer transistor preparation method

The invention provides a nanometer heterostructure preparation method comprising the following steps: providing a support structure, forming a first carbon nanotube layer on the support structure, wherein the first carbon nanotube layer comprises a plurality of first carbon nanotubes; forming a semiconductor layer on the first carbon nanotube layer; covering a second carbon nanotube layer on the semiconductor layer, wherein the second carbon nanotube layer comprises a plurality of second carbon nanotubes, and the extending direction of at least one second carbon nanotube mutually intersects with the first carbon nanotube extending direction; finding a group of mutually intersecting first and second carbon nanotubes, marking the group of the first and second carbon nanotubes, and removing other first and second carbon nanotubes; annealing said structure. The invention further provides a nanometer transistor preparation method employing the nanometer heterostructure.