Interfacial Resistance Characterization for Blade-Type Phase Change Random Access Memory

The blade-type phase-change random access memory (PCRAM) has recently attained considerable interest due to its potential for providing low programming current, while its interfacial resistance (IR) characteristics that play an important role in temperature and programming current for conventional PCRAMs is yet to be deeply studied. To achieve this, a completely 3-D electro-thermal and phase-transformation model with inclusions of thermal boundary resistance (TBR) and electrical IR (EIR) at different layered interfaces were developed to assess the influence of the IRs on phase-transformation kinetics. It was found that the TBR at the chalcogenide/insulation interface as well as interfacial size dominates the resulting programming current that is almost independent of the TBR and EIR at chalcogenide/heater interface. In this case, an optimized blade-type device having platinum silicide heater and superlattice insulated encapsulation was proposed, allowing for a 38% reduction on "SET" current and a 40% reduction on "RESET" current, respectively.