Fig. 1: Material characteristics of the device.
From: Bio-realistic synaptic characteristics in the cone-shaped ZnO memristive device
a The schematic illustration of the Pt/n-ZnO/SiO2–x/Pt synaptic heterostructure device via the 4-μm hole, the interface shows a close-up image of the device in the vicinity of the 4-μm hole, and the corresponding electrical set-up is also represented. b The SEM image of the 4-μm via-hole device and the place of the cross-section. c The cross-sectional image of the device in the vicinity of the via-hole taken by the TEM, where the film thicknesses can be easily defined. d High-resolution (20 nm scale) TEM image of the device interface, where cone-shaped n-ZnO semiconductor protrusions are observed. e A high-resolution (5 nm scale) TEM image, in which randomly oriented nanocrystalline n-ZnO grains with lattice fringes of ~0.52 nm are noted, corresponding to the [0001] plane of the wurtzite ZnO crystal structure. f The EDX determines the elemental analysis of each particular thin film
