A Systematic Investigation of TiN/CuxO/Cu RRAM with Long Retention and Excellent Thermal Stability

The long retention, more than 10 years at 85degC, and excellent thermal reliability memory of TiN-Cu x O-Cu (with TiN cap layer as top electrode) is reported. TiN cap layer results in more stable reset from low resistance state (LRS) to high resistance state (HRS) under positive pulse and SET under negative pulse, which is beneficial for providing large programming current or voltage on the resistive random access memory (RRAM) resistor connected in series with a select transistor. Results show that the structure of TiN-Cu x O-Cu with its compatibility to CMOS technology appears a promising memory device for embedded application.