Scalability of PCMO-based resistive switch device in DSM technologies

This work systematically explores the relationship between the resistive switching properties of Pr_0.7Ca_0.3MnO₃ (PCMO) thin film element and its geometry dimensions in deep submicron (DSM) technologies. A series of PCMO-based resistive switch devices (RSDs) with different geometry sizes were fabricated. Our E-test results show that by reducing the PCMO layer thickness from the normal value of about 200 nm to 30 nm, a low switching voltage (within ±2.5 V) can be achieved. The reduction of PCMO layer thickness does not incur visible impact on device reliability: no significant degradation of two resistance states was observed after 1500 programming cycles. Based on the extrapolation from the measured electrical parameters of PCMO-based devices, we analyzed the design requirements of PCMO-based resistive memory with different cell structures in sub-100 nm technologies. Our simulations show that one-transistor-one-RSD (1T1R) cell structure can be successfully scaled down to 22 nm technology node. However, the scaling of one-non-ohmic-device-one-RSD (1N1R) cell structure is significantly limited by the low driving ability of current non-ohmic device technology.