A new precursor route for the growth of NbO 2 thin films by chemical vapor deposition.

Niobium dioxide (NbO 2 ) exhibits metal-insulator transition (Mott transition) and shows the potential for application in memristors and neuromorphic devices. Presently growth of NbO 2 thin films requires high-temperature reduction of Nb 2 O 5 films using H 2 or sophisticated techniques such as molecular beam epitaxy and pulsed laser deposition. The present study demonstrates a simple chemical route of the direct growth of crystalline NbO 2 films by chemical vapor deposition using a freshly prepared Nb-hexadecylamine (Nb-HDA) complex. X-ray diffraction studies confirm the NbO 2 phase with a distorted rutile body-centered-tetragonal structure and the film grown with a highly preferred orientation on c -sapphire. X-ray photoelectron spectroscopy confirms the +4 oxidation state. The present method offers facile growth of NbO 2 films without post-reduction steps which will be assumed to be a cost-effective process for NbO 2 based devices.