基于通过原子层沉积在 Si 上生长的 Al 掺杂 HfO2 铁电电容器的物理特性,Applied Surface Science

当前位置： X-MOL 学术 › Appl. Surf. Sci. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

基于通过原子层沉积在 Si 上生长的 Al 掺杂 HfO2 铁电电容器的物理特性
Applied Surface Science ( IF 6.3 ) Pub Date : 2019-07-01 , DOI: 10.1016/j.apsusc.2019.03.166
Silviu Vulpe , Florin Nastase , Mircea Dragoman , Adrian Dinescu , Cosmin Romanitan , Sorina Iftimie , Antoniu Moldovan , Nicoleta Apostol

摘要基于铝 (Al) 掺杂氧化铪 (HfO2) 薄膜在硅衬底上生长的铁电电容器是通过原子层沉积 (ALD) 制造的，考虑到两种方法。第一个涉及通过交替 HfO2 和 Al2O3 的 ALD 循环，以层流方式生长二元氧化物，第二个，两种前体在表面上顺序混合。已使用 X 射线光电子能谱 (XPS) 和掠入射 X 射线衍射 (GIXRD) 研究了沉积的铝掺杂氧化铪 (Al:HfO2) 薄膜的组成和结构。XPS 测量显示形成了相反的铁电极化区域。通过 GIXRD，发现沉积在 Si 上的 Al:HfO2 薄膜具有多晶畴结构。铁电畴的记录和研究通过压电响应力显微镜 (PFM) 进行，而获得的器件的电气性能通过电容-电压 (CV) 和电流-电压 (IV) 特性进行分析。PFM 测量表明，即使在写入区域之外也存在机械非零响应，并且对于适当的电应力值，连续区域之间的相位差饱和到接近 180° 的值。原子力显微镜 (AFM) 分析表明，对于所有生长的薄膜，粗糙度平均值非常低，约为 0.2 nm，厚度约为 7 nm。从 CV 特性中提取内存窗口，发现通过第一种 ALD 方法获得的器件的计算值分别为 0.8 V，对于第二种方法获得的器件，计算值分别为 0.44 V。而且，

"点击查看英文标题和摘要"

Physical properties of the ferroelectric capacitors based on Al-doped HfO2 grown via Atomic Layer Deposition on Si

Abstract Ferroelectric capacitors based on aluminium (Al) doped hafnium oxide (HfO2) thin films grown on silicon substrates were fabricated by Atomic Layer Deposition (ALD), taking into account two methods. The first one involved the growth of a binary oxide, in a laminar way, by alternating the ALD cycles of HfO2 and Al2O3, and the second, the two precursors were sequentially mixed on the surface. The composition and structure of deposited aluminium doped hafnium oxide (Al:HfO2) thin films have been studied using X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray diffraction (GIXRD). XPS measurements show the formation of opposite ferroelectric polarization areas. Via GIXRD, it was found that the Al:HfO2 films deposited on Si have a structure with polycrystalline domains. Recording and investigation of ferroelectric domains were performed by Piezoresponse Force Microscopy (PFM), while the electrical performances of obtained devices were analysed by capacitance-voltage (C-V) and current-voltage (I-V) characteristics. The PFM measurements show there is a mechanical non-zero response even outside the written area and for an appropriate value of the electrical stress the difference in phase between successive areas is saturated to a value close to 180°. The atomic force microscopy (AFM) analyses indicate a very low value of roughness average, for all grown thin films, ~0.2 nm, for a thickness of ~7 nm. From C-V characteristics, the memory window was extracted and the calculated values were found to be 0.8 V for the device obtained by the first ALD method, and 0.44 V for the second one, respectively. Moreover, in the case of the device based on the ferroelectric layer grown by the second ALD method, the memory window extends over a much wider applied voltage domain, in the range (±4 V; ±8 V), at a signal of 100 kHz.

更新日期：2019-07-01

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南