Till now electron microscopy techniques have not been used to evaluate the plasma-target interactions undergone during the magnetron sputtering process. The destructive nature of this interaction severely alters the target microstructure. Utilising quantitative microscopy techniques can shed light on the complex plasma and solid-state processes involved which can ultimately lead to improved functional thin film deposition. As a representative functional material, aluminium doped-zinc oxide (AZO) is an upcoming alternative to conventional transparent electrode wherein the process optimisation is of great importance. In this paper, we evaluate the pre- and post- sputter field emission scanning electron microscopy (FESEM) data for ceramic AZO target fabricated at three final sintering temperatures (1100C, 1200C and 1300C). In all cases, grain boundaries are merged in addition to a visible reduction in the secondary phases which makes segmentation-based image analysis challenging. Through surface statistics (i.e. fractal dimension, autocorrelation length, texture aspect ratio and entropy) as a function of magnification we can quantify the electron microscopy image of the microstructure. We show that the plasma-microstructure interaction leads to an increase in autocorrelation length, texture aspect ratio and entropy for the optimum AZO ceramic sputtering target sintered at 1200°C. Furthermore, a maximum reduction in fractal dimension span (as determined by exponential regression) is also observed for 1200C. In addition to the evaluation of plasma effects on sintering, our approach can provide a window towards understanding the underlying thin film growth mechanisms. We believe that this technique can be applied to the defect characterisation of a wide range of polycrystalline ceramic sputtering targets (e.g. ITO, CZTS, GAZO and so on) with the ultimate goal of improving the magnetron sputtering process and the resulting functional thin film. This article is protected by copyright. All rights reserved.

中文翻译：

---

磁控溅射前后陶瓷靶材的定量 SEM 表征：以氧化铝锌为例

到目前为止，还没有使用电子显微镜技术来评估在磁控溅射过程中发生的等离子体-靶材相互作用。这种相互作用的破坏性严重改变了目标微观结构。利用定量显微镜技术可以揭示所涉及的复杂等离子体和固态过程，最终可以改善功能性薄膜沉积。作为具有代表性的功能材料，铝掺杂氧化锌 (AZO) 是即将到来的传统透明电极的替代品，其中工艺优化非常重要。在本文中，我们评估了在三个最终烧结温度（1100C、1200C 和 1300C）下制造的陶瓷偶氮靶的溅射前和溅射后场发射扫描电子显微镜 (FESEM) 数据。在所有情况下，除了二次相的明显减少之外，晶界被合并，这使得基于分割的图像分析具有挑战性。通过表面统计（即分形维数、自相关长度、纹理纵横比和熵）作为放大倍数的函数，我们可以量化微观结构的电子显微镜图像。我们表明，对于在 1200°C 下烧结的最佳 AZO 陶瓷溅射靶，等离子体-微观结构相互作用导致自相关长度、织构纵横比和熵增加。此外，还观察到 1200C 时分形维数跨度的最大减少（由指数回归确定）。除了评估等离子体对烧结的影响之外，我们的方法还可以为理解潜在的薄膜生长机制提供一个窗口。我们相信，该技术可以应用于多种多晶陶瓷溅射靶材（例如 ITO、CZTS、GAZO 等）的缺陷表征，最终目标是改进磁控溅射工艺和由此产生的功能薄膜。本文受版权保护。版权所有。