Localized growth of nanotubes or nanofibers of carbon, silicon, boron or their alloys on a substrate, useful in the construction of field-effect cathodes, involves heating of a bi-layer structure

摘要

Controlled growth of nanotubes or nanofibers on a substrate is carried out as follows: (1) establishment of a bi-layer structure on a substrate consisting of a layer of catalytic material and a layer of associated material; (2) heating of the bi-layer to a high temperature to form a single alloy of catalyst/associated material; and (3) growth of nanotubes or nanofibers on the localized catalyst material. Process for the controlled growth of nanotubes or nanofibers on a substrate is carried out as follows: (1) establishment of a bi-layer structure on a substrate consisting of a layer of catalytic material and a layer of associated material, the latter being such as to form a non-catalytic alloy with the catalytic material at a high temperature; the bi-layer comprising at least one opening on the layer of associated materials so as to comprise locally a single layer of catalyst; (2) heating of the bi-layer to a high temperature to form a single alloy of catalyst/associated material, this forming a second opening with localization of the catalytic material in this opening; and (3) growth of nanotubes or nanofibers on the localized catalyst material. An Independent claim is also included for the manufacture of a field-effect cathode by the technique.