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Fabrication techniques at the nanometer scale offer potential opportunities to access single dopant features in nanoscale transistors. Here we report full-band quantum transport simulations with hole-phonon interactions through a device consisting of two gates- all-around in series and a p-type Si nanowire channel with a single-dopant within each gated region. For this purpose, we have developed and implemented a mode-space based full-band quantum transport simulator with phonon scattering using the six-band k.p method. Based on the non-equilibrium Green's function formalism and the self-consistent Born's approximation, an expression for the hole-phonon interactions self-energy within the mode-space representation is introduced.

We employ an advanced three-dimensional (3D) electro-thermal simulator to explore the physics and potential of oxide-based resistive random-access memory (RRAM) cells. The physical simulation model has been developed recently, and couples a kinetic Monte Carlo study of electron and ionic transport to the self-heating phenomenon while accounting carefully for the physics of vacancy generation and recombination, and trapping mechanisms. The simulation framework successfully captures resistance switching, including the electroforming, set and reset processes, by modeling the dynamics of conductive filaments in the 3D space. This work focuses on the promising yet less studied RRAM structures based on silicon-rich silica (SiOx) RRAMs. We explain the intrinsic nature of resistance switching of the SiOx layer, analyze the effect of self-heating on device performance, highlight the role of the initial vacancy distributions acting as precursors for switching, and also stress the importance of using 3D physics-based models to capture accurately the switching processes. The simulation work is backed by experimental studies. The simulator is useful for improving our understanding of the little-known physics of SiOx resistive memory devices, as well as other oxide-based RRAM systems (e.g. transition metal oxide RRAMs), offering design and optimization capabilities with regard to the reliability and variability of memory cells.