PhD Alumni

Lavizzari Simone

Present position: Device Engineer with Numonyx R&D, Italy

Thesis title:  Numerical Models Of Conduction, Switching And Structure Relaxation In Phase Change Memories
Advisor:  Andrea L. Lacaita
Research area:  Microelettronica e tecnologie emergenti
Thesis abstract:  
Mainstream Flash non volatile memories are predicted to face fundamental scaling limits in the next technology nodes, therefore several emerging technology have been recently proposed. Among these, Phase Change Memory (PCM) and resistive-switching RAM (RRAM) show several interesting features such fast read/write, low voltage operation and superior cyclability, as well as promising scalability.
My thesis focuses on Phase Change Memory (PCM), a new generation technology that relies on the phase-change properties of a chalcogenide material, usually Ge2Sb2Te5 (GST), which can appear in either a crystalline or an amorphous phase with resistances differing by 2–3 orders of magnitude. In detail the object of my work has been to develop a numerical tool, physical based, able to simulate transient effects involved in threshold switching and structure relaxation responsible for resistance drift. This tool has been used to predict PCMs performances/reliability and also for scaling projections at technological nodes F = 48 − 8 nm.