posted on 2024-03-18, 04:33authored byTongjun Zhang, Li Shao, Ayoub Jaafar, Ioannis Zeimpekis, Cornelis H. de Groot, Philip N. Bartlett, Andrew L. Hector, Ruomeng Huang
In response to the growing need for efficient processing
of temporal
information, neuromorphic computing systems are placing increased
emphasis on the switching dynamics of memristors. While the switching
dynamics can be regulated by the properties of input signals, the
ability of controlling it via electrolyte properties of a memristor
is essential to further enrich the switching states and improve data
processing capability. This study presents the synthesis of mesoporous
silica (mSiO2) films using a sol–gel process, which
enables the creation of films with controllable porosities. These
films can serve as electrolyte layers in the diffusive memristors
and lead to tunable neuromorphic switching dynamics. The mSiO2 memristors demonstrate short-term plasticity, which is essential
for temporal signal processing. As porosity increases, discernible
changes in operating currents, facilitation ratios, and relaxation
times are observed. The underlying mechanism of such systematic control
was investigated and attributed to the modulation of hydrogen-bonded
networks within the porous structure of the silica layer, which significantly
influences both anodic oxidation and ion migration processes during
switching events. The result of this work presents mesoporous silica
as a unique platform for precise control of neuromorphic switching
dynamics in diffusive memristors.