Thermal study of multilayer resistive random access memories based on HfO2 and Al2O3 oxides

Abstract

An in-depth analysis including both simulation and experimental characterization of Resistive RAMs (RRAMs) with dielectric stacks composed of two layers of HfO2 and Al2O3 stacked in different order is presented. The simulator, that includes the electrodes in the simulation domain, solves the 3D heat equation and calculates the device current. The results are employed to analyze thermal effects in bilayer HfO2 and Al2O3-based RRAMs with electrodes of Ni and Si-n+ during resistive switching (RS) operation. According to our simulations and the experimental data, the narrow part of the conductive filaments (CF) is formed in the HfO2 layer in all the cases and, therefore, no important differences are found in terms of reset voltage if the oxide stack order is changed with respect to the electrodes. This result is attributed to the fact that the heat flux in the Al2O3 is higher than

Temperature of Conductive Nanofilaments in Hexagonal Boron Nitride Based Memristors Showing Threshold Resistive Switching

“…The values obtained using Equation () have been compared to those obtained by solving the 3D heat equation (Equation ()) and the current equation for Ag/h‐BN/Au structures. [ 30–31 ] $$\[ \begin{array}{*{20}{c}}{\nabla ({{\rm{k}}_{TH}}(x,\,y,\,z)\nabla T(x,\,y,\,z)) + \;{{\dot{e}}_{generated}} = 0}\end{array} \]$$…”

“…The values obtained using Equation ( 1) have been compared to those obtained by solving the 3D heat equation (Equation ( 2)) and the current equation for Ag/h-BN/Au structures. [30][31] (k ( , , ) ( , , )) 0 x y z T x y z e TH generated…”

Ferroelectric Electroresistance after a Breakdown in Epitaxial Hf0.5Zr0.5O2Tunnel Junctions

“…However, XRD temperature experiments of similar films with similar composition have shown that the orthorhombic phase is stable at least up to 1000 C, 51 which is much larger than the evaluated temperature increase in similar devices. 52 Therefore, an intrinsic permittivity decrease related to a phase transformation is unlikely to occur. Alternatively, if the permittivity after the breakdown is fixed to its value before the breakdown, then, assuming the same contact area A, the effective thickness of the capacitor would be increased up to ≈ 7.7 nm.…”

Effect of Annealing Temperature for Ni/AlOx/Pt RRAM Devices Fabricated with Solution-Based Dielectric

“…As one of the promising candidates for next-generation nonvolatile memories, resistive random access memory (RRAM) has received considerable attention due to significant advantages concerning simplicity of structure, low power consumption, fast read & write speed, high scalability and 3-D integration feasibility compared to the industry standard silicon-based flash memories [1,2,3,4,5,6,7]. Current candidate materials for the resistive switching (RS) layer of RRAM devices include perovskite, ferromagnetic and metal oxide-based materials [1,3,4,5,8,9,10,11]. In particular, metal oxide-based materials such as AlO x , NiO x , TiO x and HfO x are currently extensively discussed because of the simplicity of the material [10,12,13,14].…”