Bi2O3薄膜的制备及其电阻开关特性的研究

电阻式存储器由于具有众多的优点有望成为最有前景的下一代高速非挥发性存储器的选择之一.实验利用射频磁控溅射法在重掺硅上沉积了Bi2O3薄膜,并对该薄膜的结晶状态和Au/Bi2O3/n+Si/Al结构的电阻开关特性进行了研究.XRD分析结果表明,射频磁控溅射法沉积所得的Bi2O3薄膜结晶性能好,(201)取向明显.I-V曲线测试结果表明,Au/Bi2O3/n+Si/Al结构具有单极性电阻开关特性.通过对不同厚度Bi2O3薄膜的Au/Bi2O3/n+Si/Al结构I-V特性比较发现,随着薄膜厚度的增加,电阻开关的Forming、Set和Reset阈值电压均随之增加.对于Bi2O3薄膜厚度为31.2 nm的Au/Bi2O3/n+Si/Al结构,其Forming、Set和Reset阈值电压均低于4 V,符合存储器低电压工作的要求.

Deposition of Bi2O3 Thin Films and Their Resistive Switching Characteristics

Resistive random access memory(ReRAM) is one of the most promising candidates for next generation high speed nonvolatile memory devices.Bi2O3 thin films were deposited on heavily doped silicon wafer by RF magnetron sputtering,and the crystalline structure of the Bi2O3 thin films were characterized by XRD.The resistive switching characteristics of the Au/Bi2O3/n+Si/Al structure and the dependence of the ReRAM behavior on the thickness of the Bi2O3 thin films were studied.XRD analysis shows that the Bi2O3 thin films have good crystalline quality with(201) preferential orientation,while I-V curves results indicate that Bi2O3 thin films exhibit reversible and steady unipolar resistive switching behaviors.It is further found that the forming voltages,set voltages,and reset voltages depend linearly on the thickness of Bi2O3 thin films,and for the device with the thickness of 31.2 nm,these three threshold voltages are all below 4 V,which meet the need of low voltage operation of the memories.