论文标题
在低温温度下沉积的无定形超宽带隙ZNOX薄膜
Amorphous ultra-wide bandgap ZnOx thin films deposited at cryogenic temperatures
论文作者
论文摘要
晶体Wurtzite氧化锌（W-ZNO）可用作宽带间隙半导体，用于发光设备以及透明或高温电子。在这些应用中，使用无定形氧化锌（A-ZNO）可能是一个优势。在本文中，我们报告了X射线无定形的A-ZNOX薄膜（〜500 nm）通过反应性磁控溅射沉积在低温温度下。在沉积过程中，通过通过铜底物持有人的氮流冷却底物。膜的特征是X射线衍射（XRD），拉曼，红外，UV-VIS-NIR光谱和椭圆法。玻璃和Ti底物上的A -ZNOX膜在底物持有器温度约为-100 OC下获得。通过FTIR光谱检测到A-ZNOX膜中的201、372和473 cm-1以及O-H拉伸和弯曲吸收带的新振动带。拉曼光谱在386和858 cm-1处显示出特征性的ZnO2峰，分别归因于过氧化物离子O22-拉伸和库模式。此外，膜包含中性和离子化的O2和O2种。 A-ZNOX膜在可见光范围内高度透明（约87％），在2.25 eV（550 nm）时表现出1.68的折射率。光条间隙为4.65 eV，在3.50 eV处具有额外的带边缘吸收功能。已经表明，积极冷却底物的沉积可能是获得无法在室温下沉积的低温相的合适技术。
Crystalline wurtzite zinc oxide (w-ZnO) can be used as a wide band gap semiconductor for light emitting devices and for transparent or high temperature electronics. The use of amorphous zinc oxide (a-ZnO) can be an advantage in these applications. In this paper we report on X-ray amorphous a-ZnOx thin films (~500 nm) deposited at cryogenic temperatures by reactive magnetron sputtering. The substrates were cooled by a nitrogen flow through the copper substrate holder during the deposition. The films were characterized by X-ray diffraction (XRD), Raman, infrared, UV-Vis-NIR spectroscopies, and ellipsometry. The a-ZnOx films on glass and Ti substrates were obtained at the substrate holder temperature of approximately -100 oC. New vibration bands at 201, 372, and 473 cm-1 as well as O-H stretch and bend absorption bands in the a-ZnOx films were detected by FTIR spectroscopy. Raman spectra showed characteristic ZnO2 peaks at 386 and 858 cm-1 attributed to the peroxide ion O22- stretching and libration modes, respectively. In addition, the films contain neutral and ionized O2 and O2- species. The a-ZnOx films are highly transparent in the visible light range (approx. 87%) and exhibit a refractive index of 1.68 at 2.25 eV (550 nm). An optical band gaps is 4.65 eV with an additional band edge absorption feature at 3.50 eV. It has been shown that the deposition on actively cooled substrates can be a suitable technique to obtain low temperature phases that cannot be deposited at room temperature.
