3-D Resistance Model for Phase-Change Memory Cell

In this paper, a 3-D resistance model is proposed for phase-change (PC) memory cell based on cell geometry and RESET current. Explicit expression is developed for PC radius in terms of RESET current, cell geometry, and material property. Conformal mappings are used for SET and RESET resistance calculation in 2-D models, which solve the problem of current crowding in structures with complex boundary condition. In the 3-D model development, additional spreading resistance is considered, together with the bulk resistance stemmed from 2-D model to form the eventual complete expression. Models show good consistency with finite element simulation and experimental data.