The disclosed technology generally relates to semiconductor devices and more particularly to selector devices for memory devices having a resistance switching element, particularly resistive random access memory (RRAM) devices. In one aspect, a selector device includes a first barrier structure comprising a first metal and a first semiconductor or a first low bandgap dielectric material, and a second barrier structure comprising a second metal and a second semiconductor or a second low bandgap dielectric material. The selector device additionally includes an insulator interposed between the first semiconductor or the first low bandgap dielectric material and the second semiconductor or the second low bandgap dielectric material. The first barrier structure, the insulator, and the second barrier structure are stacked to form a metal/semiconductor or low bandgap dielectric/insulator/semiconductor or low bandgap dielectric/metal structure.