Understanding amorphous states of phase-change memory using Frenkel-Poole model

A method based on Frenkel-Poole emission is proposed to model the amorphous state (high resistance state) in mushroom-type phase-change memory devices. The model provides unique insights to probe the device after amorphizing (RESET) operation. Even when the resistance appears the same under different RESET conditions, our model suggests that both the amorphous region size and the defect states are different. With this powerful new tool, detailed changes inside the amorphous GST for MLC operation and retention tests are revealed.