Parallel multi-confined (PMC) cell technology for high density MLC PRAM

We first present a parallel multi-confined (PMC) cell structure on single contact was successfully integrated by using CVD PCM process. PMC cell shows the discrete four resistance levels with increasing applied current, and its middle resistances (D01, D10) have the low drift coefficient under 0.007. The four resistance levels were maintained up to 2E5 cycles. From simulation results, PMC cell structure is applicable to MLC PRAM device below 25nm design rule.