Modeling and Simulation of RRAM With Carbon Nanotube Electrode

The resistive random access memory with metallic carbon nanotube (CNT-RRAM) electrode possesses low power consumption and low junction temperature. In this work, both physical and compact models describing the operations of CNT-RRAM at the microscopic level are presented. In the physics-based model, the migration of oxygen vacancies is described by fully coupled oxygen transport, current continuity, and heat conduction equations, with a proper finite element based numerical solver utilized to solve them. The accuracy of the physical model is verified by comparing the simulated I-V curves with experimental results. After that, a 1T1R memory cell architecture composing of the CNT-RRAM and a vertical MOSFET switch is developed, and a compact model is proposed to characterize its electric properties. The I-V curves obtained by the compact model agree well with experimental data. The results indicate that the proposed models can accurately account for the set/reset characteristics of CNT-RRAM, which would be beneficial for the optimal design of devices and circuits.