Effect of downsizing and metallization on switching performance of ultrathin hafnium oxide memory cells

This paper explores the suitability of atomic layer deposited hafnium oxide (HfO₂) based resistive oxide memories for their integration into advanced embedded non-volatile memory technology nodes at 28 nm and below. Downscaling trends in advanced CMOS semiconductor technology and novel user needs require high packing density, lower power consumption, faster read-write with enhanced reliability features. Two terminal resistive memory layers, which were produced under optimized atomic layer deposition conditions have been investigated in terms of these features in addition of downscaling and cost-effective production. The experimental results are focused on downscaling issue of HfO₂ based oxide RAMs with an emphasis on structure and electrode metallization dependent resistive switching of Metal/HfO₂/Metal memory stacks and associated physical and electrical characteristics. The role of the metallization, microstructure and dielectric properties were determined to have better insight into the switching performance. Finally, a memory cell array test platform was set up using a 4k 1T1R cell array architecture and its suitability was demonstrated for testing the performance of resistive memory cells for advanced technology nodes.