Engineering cationic defects in transparent tin oxide superlattices

The lack of understanding in engineering cation defects in metal oxides has impeded the development of high performance, and transparent electronic devices. Through studying the formation energy of various cationic defects in Mn-doped SnO₂ via simulation, we found Mn³⁺ cations occupy the interstitial sites of SnO₂ nanocrystals, and we proved that such defects can be engineered to significantly improve resistive switching performance of tin oxide-based devices. With this finding, a new solution-processed approach has been developed to synthesize Mn-doped SnO₂ nanocrystals with a self-assembly technique for high quality transparent Mn-doped SnO₂ thin film fabrication. Defect migration behavior of the Mn-doped SnO₂ thin film was studied by building a metal-oxide-metal sandwich device. The effects of cationic defects, such as Mn interstitials, on the charge transport behavior were further studied to reveal the underlying mechanism. This study provides new insights into the design and engineering of defects in transparent oxides for high-density data storage applications.