Ultrathin Al1−x Sc x N for Low‐Voltage‐Driven Ferroelectric‐Based Devices
Ultrathin Al1−x
Sc
x
N for Low‐Voltage‐Driven Ferroelectric‐Based Devices
复制标题
超薄 Al1−x
DOI：
--
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
S. Fichtner
中科院分区：
文献类型：
--
作者：
Georg Schönweger;Md. Redwanul Islam;N. Wolff;A. Petraru;L. Kienle;H. Kohlstedt;S. Fichtner
Al 1 −x Sc x N铁电性的厚度缩放是其在神经形态计算和存储设备中潜在应用的决定性因素。在这封信中，报道了在室温下铁电开关的GaN（10 nm）Al0.72Sc0.28N薄膜。通过磁控溅射在GaN/蓝宝石衬底上生长全外延Al0.72Sc0.28N/Pt异质结构，然后通过原位Pt覆盖方法来避免Al0.72Sc0.28N薄膜表面的氧化。通过X射线衍射和透射电子显微镜的结构表征揭示了所建立的外延。由此获得的高质量薄膜与原位覆盖相结合，促进了Al 1 −x Sc x N的铁电切换。的相对介电常数和矫顽场的依赖关系上的Al0.72Sc0.28N膜厚度的分析表明，从100 nm到10 nm的范围内只有适度的缩放效应，这表明铁电性的临界厚度尚未接近。此外，沉积的层堆叠证明了使用溅射沉积技术将外延铁电Al 1 −x Sc x N包括到全外延GaN基器件中的可能性。因此，强调了全外延Al 1 −x Sc x N的集成和缩放潜力，其提供了最先进的铁电存储器件所需的高存储密度和低电压操作。
Thickness scaling of ferroelectricity in Al1−x Sc x N is a determining factor for its potential application in neuromorphic computing and memory devices. In this letter, ultrathin (10 nm) Al0.72Sc0.28N films that are ferroelectrically switchable at room temperature are reported on. All‐epitaxial Al0.72Sc0.28N/Pt heterostructures are grown by magnetron sputtering onto GaN/sapphire substrates followed by an in situ Pt capping approach to avoid oxidation of the Al0.72Sc0.28N film surface. Structural characterization by X‐Ray diffraction and transmission electron microscopy reveals the established epitaxy. The thus‐obtained high‐quality films in combination with in situ capping facilitate ferroelectric switching of Al1−x Sc x N in the ultrathin regime. The analysis of the relative permittivity and coercive field dependence on Al0.72Sc0.28N film thicknesses in the range from 100 nm down to 10 nm indicates only moderate scaling effects, suggesting that the critical thickness for ferroelectricity is not yet approached. Furthermore, the deposited layer stack demonstrates the possibility of including ultrathin ferroelectric Al1−x Sc x N into all‐epitaxial GaN‐based devices using sputter deposition techniques. Thus, the integration and scaling potential of all‐epitaxial ultrathin Al1−x Sc x N offering high storage density paired with low‐voltage operation desired for state‐of‐the‐art ferroelectric memory devices are highlighted.
影响因子：
3.2
作者：
Fichtner, Simon;Wolff, Niklas;Wagner, Bernhard
通讯作者：
Wagner, Bernhard
影响因子：
6.1
作者：
Fichtner, Simon;Reimer, Tim;Wagner, Bernhard
通讯作者：
Wagner, Bernhard