Epitaxial Aluminum-on-Sapphire Films as a Plasmonic Material Platform for Ultraviolet and Full Visible Spectral Regions

• DOI: 10.1021/acsphotonics.7b01366
• Publication Date: 2018-01-31T03:09:53Z
• Authors: Chang-Wei Cheng; Yun-Jhen Liao; Cheng-Yen Liu; Bao-Hsien Wu; Soniya S. Raja; Chun-Yuan Wang; Xiaoqin Li; Chih-Kang Shih; Lih-Juann Chen; Shangjr Gwo
• Keywords: Ultraviolet; Visible spectrum

In comparison to noble metals (gold and silver), aluminum is a sustainable widely applicable plasmonic material owing its abundance in the Earth's crust compatibility with complementary metal–oxide–semiconductor (CMOS) technology for integrated devices. Aluminum (Al) has superior performance ultraviolet (UV) regime lowest loss good full visible regime. Furthermore, films can remain very stable ambient environment due formation of surface native oxide (alumina) acting as passivation layer. this work, we develop an epitaxial growth technique forming atomically smooth on transparent c-plane (0001) sapphire (Al-on-Sapphire, ALOSA) by molecular-beam epitaxy (MBE). The MBE-grown ALOSA have small losses enable us fabricate utilize high-quality nanostructures variety optical configurations (reflection, transmission, scattering). Here, roughness crystal orientation are characterized atomic force microscopy (AFM) X-ray diffraction (XRD). Moreover, layer abrupt heterointerfaces investigated transmission electron (TEM). We also measured dielectric function using spectroscopic ellipsometry (SE). These results show that structural properties grown MBE excellent compared polycrystalline other deposition methods. To illustrate capability device applications spectrum, demonstrate clear plasmon polarition (SPP) interference patterns series double-groove interferometer structures varied groove–groove separations under white-light illumination. Finally, zinc (ZnO) nanowire indium gallium nitride (InGaN) nanorod (blue green) lasers prepared Al films. lasing thresholds comparable best available data obtained Ag According these result, suggest versatile platform UV spectral regions.