Study On ReRAM Based On Matal Oxides And Their Stability

With the development of electronics industry, the demand for portable productions is growingexponentially. Electronic devicessuch as cell phones, hard disk drives, MP3s and notebook/laptops, have become an indispensability tools in our daily life. The properties of memorieswhich are important parts of these potable productions become a hot subject. In order to meet therequirements of low power consumption, miniaturization and high speednew type of memories areneeded. As the feature size of flash memory continue to shrink, and the gate oxide thickness alsobeen reduced, the leakage current increases rapidly, thus affecting the stability of the device andreliability. It is very hard to improve the density of the flash memory and the high powerconsumption will obstruct its development too. Currently people have developed a variety of newnon-volatile memory, such as ferroelectric memory （FeRAM）, magnetic memory （MRAM）,phase-change memory （PCRAM）, resistive memory （ReRAM）, etc., which have both resistivememory read and write speed, low energy consumption, simple structure, high density, low cost,non-volatile, good compatibility with conventional CMOS processes and other advantages, isexpected to become the next generation of general-purpose memory.Because the I-V characteristics testing device is too complicated and expensive, thisexperiment will design a simple testing device of thin films resistive switching I-V characteristics,which is easier to realize, more convenient to carry and more cheap on cost, so it is very fit for thestudy of laboratory. This testing device mainly achieved:（1） Output a analog voltage whichgradually become the big at the both ends of the component, and the Precision is less than0.05V.（2） Detect the voltage variation of the component and receive the feedback voltage.（3） Accordingto the state of the component, change the current-limiting protection resistance automatically.（4）Judge the conditions of the cycle or stop and complete the accumulation of the counting.In this paper, Bi₂O₃thin films of different thickness were deposited by RF magnetronsputtering method. The resistive switching and stability were tested by this device. The resultsshow that: Bi₂O₃thin films fabricated by magnetron sputtering method all exhibit reversible andsteady unipolar resistive switching behaviors, and the Set voltage, Reset voltage, Reset current andReset power were all linearly increased with the thickness of thin films. Moreover, the number ofreplications of resistive switching was increased too, when the time of deposition was increased at acertain value, the increased rate of replications become decreased.