Fig. 1.

Resistive memory based on native oxide of SnSe. a Basic orthorhombic crystal structure of SnSe. b The schematic of SnSe oxidation process for two different thickness results in SnO_x resistive memory and SnO_x/SnSe/SnO_x resistive memory. The X-ray photoelectron spectroscopy (XPS) results of native oxide of SnSe and pristine SnSe for (c) O and (d) Sn peaks. The native oxide of SnSe is the mixture of SnO₂ and SnO. e The optical image and atomic force microscope (AFM) thickness profile for a 100 nm SnO_x/SnSe/SnO_x device. The scale bar is 5 μm. f Typical switching behavior of SnO_x/SnSe/SnO_x resistive memory with distinct two-step set and reset processes. g The optical image and AFM thickness profile for a 20 nm SnO_x device. The scale bar is 5 μm. h Typical switching behavior of SnO_x based resistive memory with regular one set and reset processes