Ultraviolet-electrical erasing response characteristics of Ag@SiO2 core-shell functional floating gate organic memory

In the current research of organic memory devices, optimizing the functional layers or introducing appropriate auxiliary operation signals have become two high-profile solutions for device performance optimization. In this work, floating-gate organic memory (FGOM) based on Ag@SiO2 core-shell nanospheres as the integrated floating gate-tunneling layer are studied. The device with an average thickness of 5 nm silica shell layer exhibits ideal storage characteristics under electrical pulse programming/erasing (P/E) operations. Meanwhile, appropriate incident light with different wavelengths are also applied on the device for optimizing erasing response. The best and reliable nonvolatile memory characteristics are achieved in the one erased by the ultraviolet-assisted electrical pulse, which includes nearly 24 V memory window after 104 s (charge retention rate approximate to 66%) and nearly 103 on/off current ratio. By assisting the electrical erasing pulse with the ultraviolet light, a large number of photogenerated carriers can be easily transferred through the thin shell-type tunneling layer and stored. Moreover, the device that only applies the ultraviolet signal to erase also exhibits obvious data discrimination and ideal data retention ability. It stores the optical data while identifying the optical signal, which provides a new realization idea for the integration of ultraviolet light sensor and memory devices.