On pairing bipolar RRAM memory element with novel punch-through diode based selector: Compact modeling to array performance

To reduce sneak currents in high density non-volatile Bipolar RRAM technology the bipolar selector diode with high on-current density and larger on-off current ratio is required. Recently, we have experimentally demonstrated an n+/p/n+ stack based epitaxial Si punch-through diode for selector application with excellent TCAD matching. This selector technology provides flexibility in on-voltage (V_on), on-current (I_on) and on-off current ratio. Here we present a performance evaluation of bipolar RRAM array using NPN selector. First we develop a compact circuit model of the novel punch-through diode. Second we develop a methodology of pairing a specific NPN selector with a bipolar RRAM memory based on cross-point requirements. SPICE implementation based array performance analysis shows an optimal cross-point on-off current ratio (e.g. 3×10⁴ for 1M array) for minimum array power.