利用原子层沉积方法制备了高介电常数材料(HfO2)0.8(Al2O3)0.2薄膜基电荷俘获型存储器件,并对器件的电荷存储性能做了系统研究.利用高分辨透射电子显微(HRTEM)技术表征了(HfO2)0.8(Al2O3)0.2薄膜的形貌、尺寸及器件结构.采用4200半导体分析仪测试了存储器件的电学性能.研究发现,存储器件在栅极电压为±8V时的存储窗口达到3.5V;25℃,85℃和150℃测试温度下,通过外推法得到,经过10年的数据保持时间,存储器件的存储窗口减小量分别为17%,32%和48%;(HfO2)0.8(Al2O3)0.2薄膜基电荷俘获型存储器件经过105次写入/擦除操作后的电荷损失量仅为4.5%.实验结果表明,利用高介电常数材料(HfO2)0.8(Al2O3)0.2薄膜作为存储层能够提高器件的电荷俘获性能,具有良好的应用前景.
Charge storage characteristics of High-k(HfO2)0.8(Al2O3)0.2 film based charge trapping memory devices,which were fabricated by atomic layer deposition,were systematically investigated.Employing the high-resolution transmission electron microscopy(HRTEM),the paper analyzes the morphology of the(HfO2)0.8(Al2O3)0.2 film,size and the device structure;the electrical characteristics of the memory device was measured by using the 4200 semiconductor parameter system.It is observed that the memory window is 3.5V at the sweeping gate voltage ±8 V;At 25 ℃,85 ℃ and 150 ℃,the extrapolation of the experimental results show that the charge loss after ten years were 17 %,32%,and 48 %,respectively.For the(HfO2)0.8(Al2O3)0.2 film-based charge trapping memory device,the memory window is degraded by 4.5% after 105 Write/Erase cycles.The results demonstrate that using the(HfO2)0.8(Al2O3)0.2 film as charge trapping layer can enhance the memory storage and it will be a potential candidate in future nonvolatile flash memory device application.