For New Media, Film And Process For Resistance Switching Memory

With the rapid development of portable electronic devices,the traditional silicon-based memory devices will not meet the huge market demand with the strict requirements of high density and low cost.Hence,at present,the memory device industry and many research groups have started another research tide on novel memory devices.Some novel memory devices are developed based on ferroelectric, magnetoresistive and phase change materials and some have their niches in the memory market.However these new technologies are still confined with the complicated processes and high cost before manufacturing.To fabricate a universal memory device with low cost,simple process,excellent memory performance and reliability,the electrical induced resistive switch RAM is coming under the spotlight. Up to now,most of groups focus on the transition metal oxide materials,due to their better memory performance.Novel Resistive switch RAM is considered to be the promising candidate for the next generation memory device in 2013.In this paper,we fabricated three types of thin films through interface reaction, which can be employed as the functional layer in RRAM devices while also analyzing the composition of these films.Furthermore,we did some parameter optimization trials to improve the memory device performance,and finally realized two kinds of memory devices with good nonvolatility.With the analysis based on the characterization measurements,we proposed a reasonable reaction path to form the functional films.Besides,combined with the conductive model fitting,a detailed explanation was brought up on the switching mechanism of memory devices under electrical stress.Although this technology is still at the original stage,we came up with a new perspective and approach to fabricate RRAM devices with low cost.The specific experiments and results are listed as follows:1.We created a CuSCN composite film through solid-solid interface reaction,with all kinds of characterization methods analyzed the composition of the composite and finally fabricated nonvolatile rewritable and erasable memory devices with M-S-M sandwich structure.In addition,a reasonable reaction mechanism of the composite film formation was concluded.Besides the resistive switching was ascribed to the filament formation-rupture mechanism.2.A high-qualified thiocyanogen-precursed functional composite film was created through solid-liquid interface reaction in(SCN)₂ alcohol solution,ruling out the influence of KOH during solid-solid process.Through the optimized combination of concentration and immersing time,we improved the quality of the composite film and realized bistable memory devices with better performance than through solid-solid process.With the solid-liquid process,a successive 400 write-read-erase-read cycles were observed with a high On/Off ratio up to 10000.3.Cu-DMcT metal coordination polymer film was created through self-assembly interface reaction.An excellent WORM memory characteristic was observed on these devices based on as-deposited Cu-DMcT polymer films.The WORM memory performance was improved by optimizing the combination of solvent, concentration and immersing time.Under the best parameter combination,the On/Off ratio can reach 10 exp 7 times with a high product yield.Furthermore, with the fitting method,a deep analysis was concluded on the jumping process.