柔性弯曲BaTiO3薄膜及其阻变存储器设计

摘要：在外电场作用下，很多半导体和绝缘体薄膜材料都会产生阻变现象。阻变随机存储器正是利用了材料在两个稳态阻值之间的转变来进行信息的存储。这类器件结构简单，操作速度快，功耗低，集成度高，有望代替目前广泛使用但发展到瓶颈期的Si基闪存。

钙钛矿陶瓷和单晶体的通常硬而脆，因为它们的最大弹性应变很小。而本次实验使用脉冲激光沉积法，成功在10m厚的云母衬底上以SrRuO3(SRO)作缓冲层生长出大面积BaTi0.95Co0.05O3(BTCO)薄膜，其弯曲半径可达1.4mm，在波长500-800nm的可见光范围内呈现半透明状态。Mica/SRO/BTCO/Au存储单元显示出双极性阻变行为，高低阻态开关比高达50。在2.2mm的半径下经过360,000次擦/写循环或者以3mm的半径弯曲10,000次，其阻变性能没有明显改变。最重要的是，样品可以在25-180℃范围内或经过500℃高温退火后正常工作。这类柔性半透明氧化物阻变存储器在可穿戴设备和柔性显示屏领域有很好的应用前景。

关键词：阻变随机存储器；无机；半透明；柔性

Abstract：In an external electric field, many semiconductor and insulator materials will emerge resistive switching characteristics and is able to prepare a resistive random access memory(RRAM). This device has simple structure, fast operation time, low power consumption, high-density integration and is expected to replace the widely used Si-based flash memory , which has been in the bottleneck period .

Perovskite ceramics and single crystals are commonly hard and brittle due to their small maximum elastic strain. Here the large-scale BaTi0.95Co0.05O3 (BTCO) film with SrRuO3 (SRO) buffered layer on the 10-m-thick mica substrate by PLD method is flexible with a small bending radius of 1.4 mm and semitransparent for visible lights with 500-800 nm wavelengths. Mica/SRO/BTCO/Au cells show bipolar resistive switching and the high/low resistance ratio is up to 50. The resistive switching properties do not show obvious change after the memory with 2.2 mm bending radius underwent write/erase for 360, 000 cycles or it was bent to 3 mm radius for 10, 000 times. Most importantly, the memory works properly at 25-180 °C or after it was annealed at 500 °C. The flexible and semitransparent oxide resistive memory has good prospect to be applied in smart wearable devices and flexible display screens.

Key words: resistive random access memory; inorganic; semitransparent; flexible

第一章绪论...1

1.1引言.1

1.2阻变存储器2

1.2.1RRAM的结构、原理.2

1.2.2RRAM性能参数.2

1.2.3RRAM的电阻转变机制.3

1.3有关柔性可弯曲器件的研究...5

1.3.1柔性可弯曲设备的力学性能5

1.3.3柔性和可拉伸氧化物器件的制造方法8

1.4柔性阻变存储器..10

1.4.1无机材料制备柔性阻变存储器..10

1.4.2有机材料制备柔性阻变存储器..11

1.5本文主要研究内容...12

第二章实验方法与性能测试..13

2.1脉冲激光沉积法制备薄膜.13

2.1.1设备介绍...13

2.1.2PLD薄膜制备原理...14

2.1.3主要工艺参数对薄膜生长的影响..14

2.1.4生长条件15

2.2微观结构表征..15

2.2.1X射线衍射分析15

2.2.2原子力显微镜分析..17

2.2.3紫外-可见分光计.18

2.3.4电流源表Keithley2635A...19

第三章实验数据分析...20

3.1制备薄膜材料的选取...20

3.2薄膜结构性能表征...21

3.3对BTCO薄膜阻变行为的研究..23

3.3.1薄膜厚度对阻变性能的影响...26

3.3.2弯曲对阻变性能的影响...27

3.3.3辐照对阻变性能的影响..30 柔性弯曲BaTiO3薄膜及其阻变存储器设计:http://www.youerw.com/cailiao/lunwen_203904.html