A High Density and Nano-Sized ReRAM Crossbar Array Using Copper Chemical Displacement and Nanotip Array Techniques (I)

Among candidates of next-generation nonvolatile memories, the resistive random access memory (ReRAM) has stood out due to its high shrinking capability, simple structure, and compatible with CMOS technology. To meet the requirement of market, we will develop “Copper (Cu) Chemical Displacement Technique (CDT)” and “SiO2 Nanotip Structure” techniques in application to the high density and high performance nanoscale crossbar array ReRAM in this project. This project is planned for a 3-year schedule as follow: The 1st year: For the research of “Cu CDT process”, the fabrication conditions of Cu CDT will be studied to build up the standard process of displacement rates. The switching characteristics of the Cu/SiO2-stacked ReRAM by Cu CDT on SiO2 film will be investigated. In addition, based on our preliminary study of Si nanotip structure, the schottky rectifying characteristics of the Cu CDT and n-type Si nanotip interface will also be examined. Finally, to realize the switching characteristics of 1 Diode-1 ReRAM (1D-1R), the Cu/SiO2-stacked ReRAM incorporated with the Cu CDT-nanotip diode will be carried out and studied. For the research of “SiO2 nanotip structure”, we will develop and build up the standard process of nitride-capped SiO2 nanotip structure. The 2nd year: Continuing 1st year studies, the research results of CDT-fabricated ReRAM and CDT-fabricated Cu/N+ Si-stacked schottky contact will be integrated to form 1D-1R devices. We will analyze their electrical properties and feasibility assessment of devices integrations. In addition, SiO2 nanotip structure with Cu directly grown by Cu CDT to form nanoscale ReRAM will also be investigated in 2nd year. The 3th year: Based to the results of last two years, the CDT-fabricated Cu/N+ Si-stacked schottky contact and CDT-fabricated Cu/SiO2-stacked nanoscale ReRAM (displaced SiO2 nanotip structure) will be integrated to form a high-density and high-performance nonvolatile memory crossbar array. The research results of this project will be helpful to the development of high-density and nanosized memory crossbar array by skipping the limitation of lithography technology.