Fabrication and modeling of resistance switching cells for ReRAM applications

M. Pawlikiewicz, T.S. Kalkur
University of Colorado Colorado Springs,
United States

Keywords: ReRAM, resistance switching, metal-insulator-metal, SPICE model, hysteresis, Schmitt trigger

Summary:

This paper presents the technology, fabrication process, measurements and SPICE-compatible modeling of resistance switching devices. Those devices were built using nickel oxide (NiO) as for oxide layers between two platinum layers that were used as metal electrodes. Existing processing steps had to be improved in order to obtain correct current-voltage characteristics of resistance switching devices. Such devices can be implemented in so called Resistive Random Access (ReRAM) types of memory. To use it in the ReRAM circuit design the correct model needed to be created that could be used by commercial simulators. Such model was created based on the Schmitt trigger design and was fitted to the actual measurements by adding some circuit elements and tweaking the parameters of MOSFET models. This model behaves very similarly to the physical cell under triangular voltage sweep (TVS) excitement and its I-V characteristic resembles the hysteresis. For this reason it could be applied in the ReRAM circuit design.