J. Hajto et al., METAL-SEMICONDUCTOR TRANSITION IN ELECTROFORMED CHROMIUM AMORPHOUS-SILICON VANADIUM THIN-FILM STRUCTURES, Philosophical magazine. B. Physics of condensed matter. Structural, electronic, optical and magnetic properties, 69(2), 1994, pp. 237-251
The electrical properties of electroformed Cr/hydrogenated amorphous S
i/V thin-film analogue memory structures change from a semiconducting
behaviour to a metallic behaviour as a result of systematically decrea
sing the resistance of the analogue memory state or changing the tempe
rature for a fixed memory state. The transition has been studied in a
temperature range from 13 to 300 K using d.c. and a.c. conductivity. T
he value of minimum metallic conductance was found to be of the order
of G(0) = 1 x 10(-3) Ohm(-1). The metal-non-metal transition is found
to be a second-order Anderson-type transition. The experimental result
s and theoretical considerations suggest that the conduction in the an
alogue memory states is restricted to a filamentary diameter of a size
of a few tens of Angstroms.