Faculty of Bioscience Engineering , Ghent University Global Campus , 119 Songdomunhwa-ro , Yeonsu-gu, 21985 Incheon , South Korea.
Department of Solid State Sciences , Ghent University , Krijgslaan 281/S1 , 9000 Ghent , Belgium.
ACS Appl Mater Interfaces. 2018 Mar 28;10(12):10304-10314. doi: 10.1021/acsami.7b17508. Epub 2018 Mar 16.
Electrically responsive plasmonic devices, which benefit from the privilege of surface plasmon excited hot carries, have supported fascinating applications in the visible-light-assisted technologies. The properties of plasmonic devices can be tuned by controlling charge transfer. It can be attained by intentional architecturing of the metal-semiconductor (MS) interfaces. In this study, the wafer-scaled fabrication of two-dimensional (2D) TiO semiconductors on the granular Au metal substrate is achieved using the atomic layer deposition (ALD) technique. The ALD-developed 2D MS heterojunctions exhibited substantial enhancement of the photoresponsivity and demonstrated the improvement of response time for 2D Au-TiO-based plasmonic devices under visible light illumination. To circumvent the undesired dark current in the plasmonic devices, a 2D WO nanofilm (∼0.7 nm) was employed as the intermediate layer on the MS interface to develop the metal-insulator-semiconductor (MIS) 2D heterostructure. As a result, 13.4% improvement of the external quantum efficiency was obtained for fabricated 2D Au-WO-TiO heterojunctions. The impedancometry measurements confirmed the modulation of charge transfer at the 2D MS interface using MIS architectonics. Broadband photoresponsivity from the UV to the visible light region was observed for Au-TiO and Au-WO-TiO heterostructures, whereas near-infrared responsivity was not observed. Consequently, considering the versatile nature of the ALD technique, this approach can facilitate the architecturing and design of novel 2D MS and MIS heterojunctions for efficient plasmonic devices.
电响应等离子体器件受益于表面等离子体激元激发热载流子的优势，在可见光辅助技术中支持了引人入胜的应用。通过控制电荷转移可以调整等离子体器件的特性。通过对金属-半导体（MS）界面的有意构建可以实现这种控制。在这项研究中，使用原子层沉积（ALD）技术在颗粒状 Au 金属衬底上实现了二维（2D）TiO 半导体的晶圆级制造。开发的二维 MS 异质结表现出显著增强的光响应性，并展示了二维 Au-TiO 等离子体器件在可见光照射下的响应时间的改善。为了避免等离子体器件中的不期望的暗电流，在 MS 界面上使用二维 WO 纳米薄膜（∼0.7nm）作为中间层来开发金属-绝缘体-半导体（MIS）二维异质结构。结果，对于制造的二维 Au-WO-TiO 异质结，获得了 13.4%的外量子效率的提高。阻抗测量证实了使用 MIS 结构来调制二维 MS 界面的电荷转移。Au-TiO 和 Au-WO-TiO 异质结构观察到从紫外光到可见光区域的宽带光响应性，而没有观察到近红外光响应性。因此，考虑到 ALD 技术的多功能性，这种方法可以促进新型二维 MS 和 MIS 异质结构的构建和设计，以用于高效的等离子体器件。
