Atomic layer deposition (ALD) is a technique capable of depositing conformal coatings in highly tortuous 3D nanostructures. One configuration that has attracted attention is nanocrystal (NC) based nanocomposite films, whereby a 3D network of randomly packed nanocrystals is infilled via ALD to yield a dense nanocomposite. In this work, we demonstrate criteria for predicting three important thermal ALD process parameters necessary to completely infill 3D NC networks: cycle number, precursor pulse time, and purge time. A description of representative pore geometry is developed using parameters of the film comprised of nanocrystals before infill, specifically NC diameter, NC volume fraction, and film thickness. This geometric description allowed for prediction of required precursor pulse times to saturate the NC film surface. A finite-difference model of water vapor transport during purging revealed that desorption kinetics can be used to predict purge times required to achieve complete infill. The model predictions show good agreement with experiments carried out by infilling films comprised of GaN NCs with ZnO by the diethylzinc/water process and films comprised of Al₂O₃ NCs with Al₂O₃ by the trimethylaluminum/water process.

中文翻译：

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建模原子层沉积工艺参数以实现致密的基于纳米晶体的纳米复合材料

原子层沉积（ALD）是一种能够在高度曲折的3D纳米结构中沉积保形涂层的技术。一种引起关注的配置是基于纳米晶体（NC）的纳米复合材料薄膜，其中通过ALD填充了随机堆积的纳米晶体的3D网络，以产生致密的纳米复合材料。在这项工作中，我们演示了用于预测完全填充3D NC网络所需的三个重要的热ALD工艺参数的标准：循环次数，前驱脉冲时间和吹扫时间。使用填充前由纳米晶体组成的薄膜参数，特别是NC直径，NC体积分数和薄膜厚度，对代表性孔的几何形状进行了描述。该几何描述允许预测所需的前驱体脉冲时间以使NC膜表面饱和。吹扫过程中水蒸气传输的有限差分模型表明，解吸动力学可用于预测实现完全填充所需的吹扫时间。模型预测表明与通过二乙基锌/水工艺用ZnO填充由GaN NCs组成的薄膜和由Al组成的薄膜进行的实验吻合良好通过三甲基铝/水工艺与Al ₂ O _3形成2 O ₃ NCs 。