Nonvolatile memory properties of Pt nanoparticle-embedded TiO2nanocomposite multilayers via electrostatic layer-by-layer assembly

It is demonstrated that notable resistive switching memory properties depending on voltage polarity (i.e. bipolar switching properties) can be obtained from the layer-by-layer (LbL) assembled multilayers based on transition metal oxides and metal nanoparticles. Cationic poly(allylamine hydrochloride) and anionic titania precursor layers were deposited alternately onto Pt-coated Si substrates using an electrostatic LbL assembly process. Anionic Pt nanoparticles (Pt(NP)) with about 5.8 nm diameter size were also inserted within the multilayers using the same interactions mentioned above. These multilayers were converted to Pt(NP)-embedded TiO(2) films by thermal annealing and the films were then coated with a top electrode. When external bias was applied to the devices, bipolar switching properties were observed at low operating voltages showing the high ON/OFF ratio (>10(4)) and the stable device performance. These phenomena were caused by the presence of Pt(NP) inserted within TMO films.