多层HfO_2/Al_2O_3薄膜基电荷陷阱存储器件的存储特性研究  

Characterization of Charge-Trap Memory Chip of HfO_2/Al_2O_3 Multi-Layers

作　　者：汤振杰[1] 殷江[2] 朱信华[2] 

机构地区：[1]安阳师范学院物理与电气工程学院,安阳455000 [2]南京大学材料科学与工程系,南京290093

出　　处：《真空科学与技术学报》2014年第12期1347-1351,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金(61176124);河南省教育厅科学技术研究重点项目(13A140021;14A140008)

摘　　要：借助脉冲激光沉积和原子层沉积系统,采用SiO2作为隧穿氧化物,Al2O3作为阻挡氧化物,制备了多层HfO2/Al2O3薄膜基电荷陷阱存储器件。实验发现,当电极偏压为±12 V时,存储窗口达到7.1 V,电荷存储密度约为2.5×1013cm-2。HfO2/Al2O3之间的界面在电荷存储过程中起着关键的作用,更多的电荷存储在界面的陷阱之上。经过3.6×104s的保持时间,25,85和150℃测试温度下,器件的电荷损失量分别为5%,12%和23.5%。线性外推实验数据得到,150℃下,经过10年的电荷损失量约为42%。器件优异的保持性能主要归因于HfO2/Al2O3薄膜之间较大的导带补偿。由此可以看出,多层HfO2/Al2O3薄膜基电荷陷阱存储器件是一种极具应用前景的电荷存储结构。The HfO2/Al2O3 multi-layers were synthesized by pulsed laser and atomic layer deposition on substrate of the p-type Si pre-coated with SiO2 layers; and a charge-trap memory chip was fabricated with SiO2 andAl2O3 as the tunneling and blocking oxides, respectively. The HfO2/Al2O3multi-layers were characterized with X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. With gate voltage sweeping in ＋ 12 V range, a large memory window of 7.1 V and a storage density of 2.5 × 10^13 cm^-2were obtained.The prelimiary results show that the high density of defects at the, HfO2/Al2O3 interfaces has a major impact on charge-capture. In addition, the charge loss, after storage in air for 10 years at a temperature below 150-（2, was experimentally estimated to be 42%. We suggest that the large conduction band offset at the HfO2/Al2O3 interfaces may explain its excellent data retention.

关 键 词：电荷陷阱存储器 多层薄膜 脉冲激光沉积 原子层沉积 能带排列 

分 类 号：O484.1[理学—固体物理]