Switching and memory effects in the electrical conductance of layered struc
tures based on rare-earth fluorides are investigated. These investigations
reveal the existence of high- and low-resistance states in structures of me
tal-insulator-semiconductor type. It is shown that the characteristics of t
he low-resistance state of such structures are described by a metal-tunneli
ng insulator-semiconductor model. (C) 1998 American Institute of Physics. [
S1063-7826(98)01311-8].