聚乙烯咔唑共价修饰黑磷纳米片及其在叠层阻变存储器中的应用

Synthesis of Black Phosphorus Nanosheets Covalently Modified with Poly(N-vinylcarbazole)and Its Application in Stacked Resistive Random Access Memory Devices

提升阻变存储器存储密度的有效方法之一是通过对活性层的简单叠加制备三维垂直堆叠器件。使用S-1-十二烷基-S′-(α,α′-二甲基-α′′-乙酸)三硫代碳酸酯(DDAT)共价接枝的二维黑磷(BP)纳米材料(BP-DDAT)作为关键的二维模板和可逆加成-断裂链转移(RAFT)试剂,成功制备了由聚乙烯基咔唑(PVK)共价修饰的黑磷纳米片(BP-PVK)。采用傅里叶红外光谱、X射线光电子能谱、紫外-可见吸收光谱等手段对BP-PVK进行了表征。PVK在BP表面的共价接枝有效地提高了BP的环境稳定性和在常见有机溶剂中的溶解度。以BP-PVK为活性层,在玻璃基底上制备了一种结构为Al/BP-PVK/Al/BP-PVK/Al的双层17×17横条阵列垂直堆叠的阻变存储器件,该器件在室温下表现出了典型的双稳态非易失性可擦写存储性能,开/关电流比超过103,良品率和均一性较高。

One of the most effective methods for improving the storage density of resistive random access memories(RRAMs)is to fabricate 3D vertical stacking devices.By using BP-DDAT(DDAT:S-1-dodecyl-S′-(α,α′-dimethyl-α′′-aceticacid)trithiocarbonate)as a key 2D template and reversible addition-fragmentation chain transfer(RAFT)reagent,a novel poly(N-vinylcarbazole)covalently functionalized black phosphorus derivative(BP-PVK)is successfully synthesized and well-characterized by infrared spectroscopy,X-ray electron spectroscopy and UV-Vis absorption spectroscopy.The environmental stability and solubility of BP nanosheets are greatly improved.Using BP-PVK as active layer,a double-layer vertically stacked RRAM memory device(17×17 stripe array)with a configuration of Al/BP-PVK/Al/BP-PVK/Al is fabricated.The as-fabricated device shows good bistable electrical switching and non-volatile rewritable performance at room temperature,with an ON/OFF current ratio exceeding 103,higher production yield of the memory devices and structural uniformity.