Boron nitride nanotubes (BNNTs) were grown on stainless-steel substrates by ball milling–annealing in an N2/H2 atmosphere. The effects of the precursor ratio and gas flow rate on the BNNT morphology were investigated. The correlations between experimental parameters and the BNNT morphology were interpreted based on tip- and base-growth modes. A study of the electrical properties of an individual BNNT showed that the contact resistances of the metal and BNNT contacts were improved by using an electroless technique. The main parameters such as resistivity, carrier concentration, and carrier mobility of the raw BNNTs suggest they have potential uses in high-power devices.
