Ag掺杂ITO/ZrO_(2)(Ag)/TiN忆阻器退火结晶过程及其对性能的影响

Crystallization process and effect on properties of Ag-doped ITO/ZrO_(2)(Ag)/TiN memristors

本文采用磁控溅射的方法,在In_(2)O_(3)掺杂的SnO_(2)(ITO)衬底上制备了Ag掺杂ZrO_(2)作为功能层的忆阻器器件ITO/ZrO_(2)(Ag)/TiN。该忆阻器在退火前后的性能有较大差异,在500℃退火60分钟的条件下具有112的最大开关比,并且长期存放后仍具有5000+s以上的稳定性。通过对电流-电压(I-V)曲线进行分析拟合,提出了一个基于空间电荷限制电流(Space charge limited current,SCLC)机制和肖特基发射(Schottky emission)机制的物理模型来解释器件的复位/设置(Reset/Set,RS)记忆行为。通过X射线衍射(XRD)和扫描电子显微镜(SEM)分析了退火对器件微观结构和形貌的影响,发现退火后薄膜Ag结晶度增加和峰强比改变。结果表明,通过磁控溅射制备的薄膜通常存在大量缺陷,退火处理可以减少溅射薄膜的缺陷,提升器件的稳定性和开关比。

In this work,the ITO/ZrO_(2)(Ag)/TiN memristor devices were prepared by magnetron sputtering method on In_(2)O_(3) doped SnO_(2)(ITO)substrate,and Ag-doped ZrO_(2)was used as their functional layers.The performance of these memristors varies significantly before and after annealing,with a maximum switching ratio of 112 after annealing at 500℃for 60 minutes,and it still maintains stability of over 5000+s after long-term storage.By analyzing and fitting the current voltage(I-V)curve,a physical model based on Space charge limited current(SCLC)mechanism and Schottky emission mechanism is proposed to explain the Reset/Set(RS)memory behavior of these memristors.The effect of annealing on the microstructure and morphology of the memristors were analyzed by X-ray diffraction(XRD)and scanning electron microscopy(SEM),indicating that the crystallinity of the thin film Ag increased and the peak intensity ratio changed after annealing.The results indicate that thin films prepared by magnetron sputtering usually have a large number of defects,and annealing treatment can reduce the defects of the sputtered thin films,improve the stability and switching ratio of the devices.