ZnO纳米线肖特基势垒紫外光检测和电阻开关随机存储的分析-凝聚态物理专业论文.docxVIP

and a back-to-back SBs structure is formed. The on/off ratio, sensitivity and gain of photocurrent is 4×105, 2.6×103 A/W, and 8.5×103, respectively. The photocurrent recovery consists of fast and slow processes. In the fast recovery process, the current can decrease exponentially to about 10-3 of photocurrent, and the average recovery time and time constant are 0.28 s and 46 ms, respectively. The photocurrent mechanism of ZnO NW SB photodetector is due to the generation of tunneling current, which is induced by the decrease of Barrier height and increase of electric field near SB interface by trapping photogenerated holes. The dependences of photocurrent on Barrier height and trapped holes are discussed, which indicate that the NW SB photodetector essentially has shorter recovery time than that of NW photodetector. In the fourth chapter we prepared with fast write speed and high-read window resistive switching memory devices. The resistance ratio of off state/on state was 106, write time is 20ns, switching hold time 104 s. The effects of surface oxygen vacancies on the tunneling barrier height were studied. The pulsed voltage was used to modify the concentration of oxygen vacancies which result in change the SB. In addition, we also analysis the factors on write and erase time, and developed the mechanism of nanowire resistance switch memory. KEY WORDS: ZnO Nanowire, Schottky Barrier, UV Detector, Resistive Switch Random Access Memory IV I 第 第 1 章 绪论 ZnO ZnO 纳米线肖特基势垒紫外光检测和电阻开关随机存储的研究 PAGE PAGE 13 PAGE PAGE 10 第 1 章 绪论 1.1 一维材料光电子器件研究进展 光电子器件的应用从简单的家庭用品到多媒体通讯系统，计算机，再到医疗系统 无不对人们的生活有着重要的影响。基于未来对光电子器件小型化和功能化的需求， 所以人们对纳米级的电子和光电子的需求是一个不断增长的状态，以期待研究人员能 够研发出更小且多功能的光电子器件。而半导体纳米线作为众多纳米材料中一个极具 应用前景并且生长合成容易控制等多方面的因素成为其中一个强有力的竞争对手正受 广泛研究，所以基于半导体纳米线构筑的光电子器件更是得到越来越多的研究人员的 关注。图 1-1 分别是利用有机半导体 P3HT 和 QT 与单根 ZnO 纳米线复合以形成异质 p-n 结。通过 P3HT 和 QT 修饰后的有机无机半导体异质光伏器件的光吸收效率明显得 到了提高，并分别对其太阳能电池参数进行了表征[1]。 图 1-1(a)是 ZnO/有机半导体纳米线光伏器件结构示意图，图(b)与(c)分别是利用 EBL 技术构筑 得到 ZnO/P3