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A robust simulation framework was developed for nanoscale phase change memory (PCM) cells. Starting from the reaction rate theory, the dynamic nucleation was simulated to capture the evolution of the cluster population. To accommodate the non-uniform critical sizes of nuclei due to the non-isothermal conditions during PCM cell programming, an improved crystallization model was proposed that goes beyond the classical nucleation and growth model. With the above, the incubation period in which the cluster distributions reached their equilibrium was captured beyond the capability of simulations with a steady-state nucleation rate. The implications of the developed simulation method are discussed regarding PCM fast SET programming and retention. This work provides the possibility for further improvement of PCM and integration with CMOS technology.

Abstract. The unfavoured signature of the rotation-aligned band associated with the prolate h 9/2 structure in 187 Tl has been identified. The deformation-aligned 11/2 − [505] band is also confirmed and extended. While the alignment properties of the 11/2 − [505] band seem to indicate that it has a similar magnitude of deformation as the prolate 186 Hg core, the signature splitting at low spin, taken together with new self-consistent calculations, suggest that it may actually be triaxial with γ ≈ −18 0 near the bandhead.

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