ZnS纳米薄膜的负微分电阻和记忆特性  

Negative Differential Resistance and Memory Characteristics of ZnS Nano-Films

作　　者：秦书超 董瑞新[1,2] 杜倩倩[1,2] 王媛[1,2] 

机构地区：[1]聊城大学山东省光通信科学与技术重点实验室,山东聊城252059 [2]聊城大学物理科学与信息工程学院,山东聊城252059

出　　处：《微纳电子技术》2014年第7期419-424,共6页Micronanoelectronic Technology

基　　金：国家自然科学基金资助项目(11375081);山东省自然科学基金资助项目(ZR2012FM026;ZR2012FL20)

摘　　要：通过激光分子束外延(LMBE)和热蒸发技术制备了基于ZnS纳米薄膜的Al/ZnS/ITO/玻璃器件,通过原子力显微镜(AFM)对ZnS表面薄膜形貌进行表征,采用Keithley 2400测量其电学特性,分别研究了扫描电压、ZnS薄膜厚度及不同温度的退火处理对器件电学特性的影响。实验结果表明:在不同的扫描电压作用下,器件均表现出稳定的负微分电阻特性,且其阻值随扫描电压的变化呈现出高低电阻两种状态,器件具有明显的记忆特性。适当减小ZnS薄膜的厚度或对器件进行400℃退火处理,均可有效减小低阻态的阻值,提高器件的峰-谷电流比率,进而优化器件的记忆特性。最后,基于能谷散射理论,对器件的负微分电阻特性进行了合理解释,理论和实验结果吻合较好。The A1/ZnS/ITO/glass devices based on the ZnS nano-films were fabricated by laser molecular beam epitaxy （LMBE） and thermal evaporation technology. The surface morphology of the ZnS thin films was characterized by atomic force microscope （AFM）, and the electrical properties were measured by Keithley 2400. The effects of the sweep voltages, thicknesses of ZnS films and different annealing temperatures on the electrical properties of the fabricated devices were investigated. The experimental results show that the fabricated devices exhibit the stable negative differential resistance characteristics under the different sweep voltages, and the resistance state can be switched sequentially between high and low resistive states with the sweep voltage. The devices have obvious memory characteristics. In addition, the appropriate decrease of the ZnS film thickness and the annealing operation at 400℃ can effectively decrease the resistance in the low resistive state and increase the peak-valley current ratio, and then optimize the memory characteristics of the devices. Finally, Based on the inter-valley scattering theory, the negative differentialresistance characteristics of the devices was explained reasonably. And the experiment results agree well with the theory.

关 键 词：ZnS纳米薄膜 负微分电阻 记忆特性 退火温度 能谷散射 

分 类 号：TB383[一般工业技术—材料科学与工程]