A system (100) for use as a selector in RRAM arrays comprises a first metal (110) / semiconductor (or low bandgap dielectric) (120) structure and a second metal (150) /semiconductor (or low bandgap dielectric) (140) structure. The system furthermore comprises an insulator (130). The insulator (130) is located in between the first metal (110) / semiconductor (or low bandgap dielectric) (120) structure and the second metal (150) / semiconductor (or low bandgap dielectric) (140) structure and the first and second metal / semiconductor (or low bandgap dielectric)structure are oriented back to back resulting in a metal (110) / semiconductor (or low bandgap dielectric) (120) / insulator (130) / semiconductor (or low bandgap dielectric) (140) / metal (150) structure.
