Conductivity and Charge Trapping After Electrical Stress in Amorphous and Polycrystalline Devices Studied With AFM-Related Techniques

In this paper, atomic force microscopy-based techniques have been used to study, at nanoscale, the dependence of the electrical properties of Al₂O₃ stacks for flash memories on the annealing temperature (TA). The electrical characterization has been combined with other techniques (for example, transmission electron microscopy) that have allowed to investigate the dependence of the stack crystallization and the Si diffusion from the substrate to the gate oxide on TA. The combination of both the analyses has allowed to explore if there is a relation between the percentage of diffused silicon and material crystallization with the conductivity and charge trapping of Al₂O₃ stacks.