Fabrication And Characterization Of Resistive Switching Memories Based On Bi₂O₃Thin Films

Memories have been applied to a variety of electronic products, and play a more and moreimportant roles in our life and work. With the rapid development of electronic techniques andintegrated circuits, new type memories are need, which meet higher performances, such as highspeed, high density, the long life, low power consumption, non-volatile and smaller size, etc.However, the current memory technology based on charge storage, such as flash memory, hasencountered serious technical bottlenecks, can not meet the rapid development of informationtechnology for ultra-high density storage requirements. In view of above-mentioned question,people began to study new non-volatile memory. At present, a new generation of non-volatilememory has developed, such as Ferroelectric Random Access Memory （FeRAM）, Phase ChangeRandom Access Memory （PCRAM）, Magnetron resistive Random Access Memory （MRAM）and Resistive Random Access Memory （ReRAM）. And among these, ReRAM due to its superiorcharacteristics including simple structure, high density, low power, fast speed, excellentscalability, and good compatibility with standard CMOS process. Therefore, it is expected tobecome one of the most promising candidates for next generation high speed nonvolatilememory devices.Bismuth oxide is an important semiconductor material, and exhibit many attractivecharacteristics. They have been attracted extensive attention. In recent years, Bismuth oxidematerial have been widely used in electronic functional materials, electrolyte materials,photoelectric material, medical composite materials, high-temperature superconducting materials,catalysts and so on. Therefore, it is necessary to study resistive switching property of Bi₂O₃thinfilms.In this paper, Au/Bi₂O₃/n+Si sandwich structure devices have been fabricated by RFmagnetron sputtering method. The influences of different process parameters on the properties ofthe thin films have been studied by x-ray diffractometer, UV-Vis spectrometer, I-V curve tracerand LCR meter etc. Based on the experimental results, the mechanism of resistive switching hasalso been discussed.The results show that: Bi₂O₃thin films fabricated by RF magnetron sputtering methodexhibit reversible and steady unipolar resistive switching behaviors, and it’s found that theforming voltage and set voltage are related to thickness and crystallinity of the thin film. The thinfilm is thicker, the voltages are greater and forming and set voltages decreased as the crystallinityincrease. The energy required for the rupture of Conductive filament in the process of reset is related to the amount of oxygen defects.