We report both the growth of carbon nanotube forests and electrical conduction on W, Ti, and TiN substrates coated with an ultra-thin Al O support layer. Varying the AlO thickness, a good electrical contact and high nanotube density is possible for a 0.5 nm AlO layer as such an ultra-thin film allows tunnelling. X-ray photoelectron spectroscopy shows that, when using these non-continuous AlO films, Fe catalyst diffuses into the conducting substrates, eventually causing growth to stop. Forests grown on ultra-thin AlO are potentially useful for applications as interconnects, supercapacitors, and heat spreaders.
Esconjauregui, S., Xie, R., Guo, Y., Pfaendler, SM-L., Fouquet, M., Gillen, R., Cepek, C., Castellarin-Cudia, C., Eslava, S., & Robertson, J. (2013). Electrical conduction of carbon nanotube forests through sub-nanometric films of alumina. Applied Physics Letters, 102(11). https://doi.org/10.1063/1.4798261