氧化镍溶胶-凝胶薄膜阻变特性研究  

Resistive Switching of Sol-Gel Deposited NiO Thin Films

作　　者：李建昌[1] 王玉磊[1] 侯雪艳[1] 巴德纯[1] 

机构地区：[1]东北大学机械工程与自动化学院真空与流体工程研究中心,沈阳110819

出　　处：《真空科学与技术学报》2013年第6期567-572,共6页Chinese Journal of Vacuum Science and Technology

基　　金：高等学校博士学科点专项科研基金项目(20100042120023);中央高校基本研业务费专项资金(N110403001)

摘　　要：用溶胶-凝胶法在ITO基片上旋涂制备了NiO薄膜,通过对ITO/NiO薄膜/GaIn器件进行伏安特性测试,研究了溶胶浓度、退火、层数以及Cu掺杂等对其电学特性的影响。结果表明:所制备NiO薄膜具有良好可重复双极电阻开关特性。其中,2%Cu掺杂0.2 mol/L溶胶、双层、400℃退火1 h制备的薄膜,阈值电压较低,约0.8 V;而开关比受以上因素影响不明显,约3×102。分析发现薄膜高阻态的荷电输运符合空间电荷限制导电机制,而低阻态为欧姆特性,阻变开关机理为阈值电场及焦耳热导致的氧空位细丝的形成与断裂。The NiO films were deposited by spin-coating of sol on glass substrates, pre-coated with indium-tin-oxides （ITO）. The impacts of the deposition conditions were studied. The NiO/ITO films were characterized with X-ray diffrac- tion and scanning electron microscopy. The I-V characteristics were measured with an ITO/NiO/GaIn（droplet）micro-de- vice. Reproducible resistive switching was observed regardless of the film growth conditions. The lowest threshold voltage, about 0.8 V, was obtained with the NiO film deposited under optimized conditions,annealed at 400℃ for 1.0 h, and 2% Cu-doping content. Little depending on the growth conditions,the on/off switching ratio was found to be about 3 × 10^2. The results show that the space charge limited conduction accounts for the charge transport of the high resistive state, while Ohm＇s law governs the low resistive state. We suggest that the formation and breakup of the conductive oxygen-va- cancy filament, possibly originated from the threshold voltage and/or Joule heating, may explain the switching mechanism.

关 键 词：溶胶凝胶法 NiO薄膜 阻变开关特性 导电机制 空间电荷限制导电 

分 类 号：O484[理学—固体物理]