Improved resistive switching properties in SiO_x-based resistive random-access memory cell with Ti buffer layer

In this work, low-power bipolar resistive switching is demonstrated in a fully complementary metal-oxide-semiconductor-compatible Ni/Ti/SiO_x/p⁺-Si resistive random-access memory (RRAM) device. The proposed device shows higher nonlinearity in the low-resistance state (LRS), lower reset current (<1 μA), and better endurance cycles in comparison with Ni/SiO_x/p⁺-Si RRAM device without the Ti insertion layer. The self-compliance properties can effectively alleviate current overshoot, thanks to Ti buffer layer acting as a built-in series resistance. TiO_x layer from oxygen scavenging ensures nonlinear current-voltage (I-V) characteristics for high-density integration in the cross-point array architecture. It is found that the thermal coefficient of Ti in the LRS provides a clue to switching mechanism underlying the hopping conduction with semiconducting behavior.