Growth and Characterization of Vacuum Evaporated MgSe Thin Films
Growth and Characterization of Vacuum Evaporated MgSe Thin Films
复制标题
真空蒸发 MgSe 薄膜的生长和表征
DOI：
10.1007/s11664-022-09999-5
复制
发表时间：
2022
影响因子：
2.1
通讯作者：
S. E. Al Garni
中科院分区：
文献类型：
--
作者：
R. A. Almotiri;A. Qasrawi;S. E. Al Garni
在此，硒化镁薄膜在真空沉积 (VD) 系统中在 10-5 毫巴的真空压力下热生长到玻璃基板上。这些薄膜在结构、形态、成分和光学上进行了表征。结果表明，VD 技术涂覆的 MgSe 薄膜由多晶 MgSe1.07（a = 5.149 Å，空间群）和 MgSe1.96（a = 6.514 Å，空间群）立方相组成。薄膜的平均粗糙度值为 13 nm。它们还表现出 2.54 eV 的直接能带隙和 3.34 eV 的间接带隙。此外，对介电特性、光导率和太赫兹截止频谱的详细研究表明了 MgSe 薄膜作为介电材料的能力。在光的近红外范围内达到高介电常数值。作为光导体，这些薄膜显示了一个红外光振荡器、两个可见光振荡器和两个紫外光振荡器，在紫外光范围内显示出最大等离激元频率为 8.19 GHz。这些振荡器的漂移迁移率在 4.57–9.67 cm2/Vs 范围内变化。此外，这些振荡器的太赫兹截止频率在 11–175 THz 范围内变化，证明了 MgSe 薄膜对于太赫兹技术问题的适用性。图形摘要
Herein, thin films of magnesium selenide are thermally grown in a vacuum deposition (VD) system onto glass substrates under a vacuum pressure of 10–5mbar. The films are structurally, morphologically, compositionally, and optically characterized. It is observed that MgSe thin films coated by the VD technique are composed of polycrystalline MgSe1.07(a = 5.149 Å, space group) and MgSe1.96(a = 6.514 Å, space group) cubic phases. The films displayed an average roughness value of 13 nm. They also exhibited a direct energy band gap of 2.54 eV and an indirect band gap of 3.34 eV. In addition, detailed studies of the dielectric properties, optical conductivity, and terahertz cutoff frequency spectra showed the ability of MgSe thin films to perform as a dielectric material. High dielectric constant values are reached in the near-infrared range of light. As optical conductors, the films displayed one IR, two visible, and two ultraviolet light oscillators showing a maximum plasmon frequency of 8.19 GHz in the UV range. The drift mobility of these oscillators varied in the range of 4.57–9.67 cm2/Vs. Moreover, the terahertz cutoff frequency for these oscillators varied in the range of 11–175 THz proofing the suitability of MgSe films for terahertz technology issues.Graphic Abstract