Dual-Layer Selector With Excellent Performance for Cross-Point Memory Applications

We demonstrate a CuS/GeSe dual-layer selector with excellent performance. This CuS/GeSe dual-layer selector exhibits ultrahigh selectivity (1.25 × 10
⁹
), high on-current drive (600 μA), ultralow off current (~100 fA), and extremely steep switching slope (<;1.4 mV/dec). This selector shows significant threshold switching behavior by introducing CuS as the ion supply layer to implant limited Cu ions into GeSe layer, to form unstable filaments at high voltage and retract Cu ions at low voltage. In addition, Cu/GeSe devices were fabricated as a comparison, showing desirable memory switching. These two devices are of great potential for cross-point memory applications.