Characteristics of current transfer in PVA films with dispersed multiwall carbon nanotubes on silicon substrates

Planar nanocomposite structures comprising poly(vinyl alcohol) films with dispersed multiwall carbon nanotubes (MWCNTs) deposited on silicon substrates and provided with aluminum contacts possess rectification properties and have asymmetric nonlinear current–voltage characteristics. Forward-biased nanocomposite structures exhibit a positive temperature coefficient of resistance (TCR) in a temperature interval of 270–350 K, whereas analogous PVA film structures without MWNTs have negative TCR values. Under reverse bias, the structures with MWNTs exhibit TCR with a sign changing from negative to positive. The observed behavior is explained in terms of the tunneling current transfer mechanism.