Opt Express. 2023 Apr 10;31(8):13503-13517. doi: 10.1364/OE.487881.
Optimizing the atomic layer deposition (ALD) process of films is particularly important in preparing multilayer interference films. In this work, a series of AlO/TiO nano-laminates with a fixed growth cycle ratio of 1:10 were deposited on Si and fused quartz substrates at 300 °C by ALD. The optical properties, crystallization behavior, surface appearance and microstructures of those laminated layers were systematically investigated by spectroscopic ellipsometry, spectrophotometry, X-ray diffraction, atomic force microscope and transmission electron microscopy. By inserting AlO interlayers into TiO layers, the crystallization of the TiO is reduced and the surface roughness becomes smaller. The TEM images show that excessively dense distribution of AlO intercalation leads to the appearance of TiO nodules, which in turn leads to increased roughness. The AlO/TiO nano-laminate with a cycle ratio 40:400 has relatively small surface roughness. Additionally, oxygen-deficient defects exist at the interface of AlO and TiO, leading to evident absorption. Using O as an oxidant instead of HO for depositing AlO interlayers was verified to be effective in reducing absorption during broadband antireflective coating experiments.
优化原子层沉积（ALD）工艺对于制备多层干涉膜尤为重要。本工作采用原子层沉积法（ALD）在 300°C 下于 Si 和熔融石英衬底上沉积一系列固定生长循环比为 1:10 的 AlO/TiO 纳米多层膜。通过椭圆偏振光谱法、分光光度法、X 射线衍射、原子力显微镜和透射电子显微镜系统地研究了这些层状膜的光学性能、结晶行为、表面形貌和微观结构。通过在 TiO 层中插入 AlO 夹层，可以减少 TiO 的结晶，同时降低表面粗糙度。TEM 图像表明，AlO 夹层的过度密集分布会导致 TiO 结节的出现，从而导致粗糙度增加。具有 40:400 循环比的 AlO/TiO 纳米多层膜具有较小的表面粗糙度。此外，AlO 和 TiO 界面处存在氧缺陷，导致明显的吸收。在宽带抗反射涂层实验中，使用 O 作为氧化剂代替 HO 沉积 AlO 夹层被证明可以有效降低吸收。
