Dependence of memory characteristics on the (ZrO2)x(SiO2)1−x elemental composition for charge trap flash memory applications
Dependence of memory characteristics on the (ZrO2)x(SiO2)1−x elemental composition for charge trap flash memory applications
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DOI：
10.1088/0268-1242/30/6/065010
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发表时间：
2015-05
影响因子：
1.9
通讯作者：
Zhenjie Tang;Xubing Lu;Yupeng Yang;Jing Zhang;D. Ma;Rong Li;Xiwei Zhang;D. Hu;Tingxian Li
中科院分区：
文献类型：
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作者：
Zhenjie Tang;Xubing Lu;Yupeng Yang;Jing Zhang;D. Ma;Rong Li;Xiwei Zhang;D. Hu;Tingxian Li
制作了以（ZrO 2）x（SiO2）1−x（x = 1.0、0.92、0.79、0.63、0.46、0.28、0.17和0.08）薄膜作为电荷捕获层的电荷捕获闪存电容器，并研究了存储窗口、数据保持和编程/擦除速度对摩尔分数x的依赖性。据观察，改变元素组成会影响（ZrO 2）x（SiO 2）1−x薄膜的介电常数和等效氧化物厚度，并且存储电容器（x = 0.63）在±10 V扫描电压范围内显示出高达10.7 V的存储窗口，并且在10年内的外推电荷损失为9.0%。当x = 0.79和0.63时，对于存储电容器可以获得更快的编程/擦除速度。这些结果应归因于不同的（ZrO 2）x（SiO 2）1−x的微观结构，缺陷态密度和能带排列的组成的变化所导致的。为了实现存储器窗口、数据保持和编程/擦除速度之间的折衷，对于电荷捕获闪存应用，（ZrO 2）x（SiO 2）1-x捕获层的最佳x值在0.63至0.79的范围内。本研究提供了有用的见解复杂氧化物为基础的电荷陷阱闪存的组成选择。
Charge trap flash memory capacitors incorporating various (ZrO2)x(SiO2)1−x films (x = 1.0, 0.92, 0.79, 0.63, 0.46, 0.28, 0.17 and 0.08) as the charge trapping layer were fabricated, and the dependence of the memory window, data retention and program/erase speed on the mole fraction value x were investigated. It was observed that changing the elemental composition affects the dielectric constant and equivalent oxide thickness of (ZrO2)x(SiO2)1−x films, and the memory capacitor (x = 0.63) exhibits a memory window as large as 10.7 V for a ±10 V sweeping voltage range, and a low extrapolated charge loss of 9.0% over a period of 10 years. A faster program/erase speed can be obtained for memory capacitors when x = 0.79 and 0.63. The results should be attributed to the different (ZrO2)x(SiO2)1−x microstructures, defect state densities and energy band alignments resulting from the change of compositions. In order to achieve the trade-off between the memory window, data retention, and program/erase speed, the optimal x values of the (ZrO2)x(SiO2)1−x trapping layer are in the range of 0.63 to 0.79 for charge trap flash memory applications. The present study provides useful insights for the composition selection for a complex oxide-based charge trap flash memory.