AVS 59th Annual International Symposium and Exhibition
    Thin Film Thursday Sessions
       Session TF-ThP

Paper TF-ThP1
Vanadium Oxide Thin Films Grown by ALD using TEMAV and O3 or H2O Precursors

Thursday, November 1, 2012, 6:00 pm, Room Central Hall

Session: Thin Film Poster Session
Presenter: A. Premkumar, IMEC, Belgium
Authors: A. Premkumar, IMEC, Belgium
M. Toeller, Tokyo Electron Limted, Japan
I. Radu, Katholieke Universitiet, Leuven, Belgium
C. Adelmann, IMEC, Belgium
M. Schaekers, IMEC, Belgium
J. Meersschaut, IMEC, Belgium
T. Conard, IMEC, Belgium
J. Malgorzata, IMEC, Belgium
S. Van Elshocht, IMEC, Belgium
Correspondent: Click to Email
Vanadium dioxide (VO<sub>2</sub>) is a smart material and offers interesting optical and electrical switching applications because of the reversible semiconductor- metal transition (SMT) that is observed at a temperature of about 68°C. Thin film growth of VO<sub>2</sub> has been extensively studied by CVD, PVD and sol-gel techniques. Aggressive scaling and increasing integration complexity have placed greater importance on atomic layer deposition (ALD) for depositing oxides in microelectronics. In this work we have developed an ALD process for VO<sub>2</sub> on 300 mm Si substrates using TEMAV precursor comparing different reactants (O<sub>3</sub> and H<sub>2</sub>O) and starting surfaces (SiO<sub>2</sub> or Al<sub>2</sub>O<sub>3</sub>). We studied the ALD process in a 100-210ºC temperature window. The as deposited films (100-150ºC) were found to be XRD amorphous. Annealing in N<sub>2</sub>/O<sub>2</sub> ambient (425-500ºC) resulted in crystalline films. For the O<sub>3</sub> based process, the VO<sub>2</sub> formation conditions were found to be strongly dependent on the substrate investigated with a narrow process window for the preparation of phase pure and continuous VO<sub>2</sub> films. In contrast, highly uniform layers with consistent phase formation pathways were observed for the water based ALD process on all the substrates investigated. Films resulting from the water based process were smoother. Growth/anneal conditions were optimized to yield a resistivity change at the SMT of two orders of magnitude for 8 nm VO<sub>x</sub> films.