Microstructure-Based Optimization of Pulsed Laser Deposited CuI Thin Films

基于在第一个资助期内令人惊讶的有希望的结果，莱比锡大学的项目工作现在将完全集中在CuI基异质结构的脉冲激光沉积（PLD）上。然而，哈勒Fraunhofer IMWS的最先进的微观结构分析技术组合不仅限于PLD生长的薄膜，而且用于整个研究单位框架内所有类型的CuI样品的表征。 通过这种方式，可以比较不同的生长方法，例如关于CuI膜的粘附性质。除了电子显微镜方法，提供上级横向分辨率（TEM），以及相当大的筛选区域（SEM，EBSD），表面分析，包括ToF-SIMS和纳米压痕将被应用。因此，后者代表了一种很有前途的技术，机械特性。PLD允许控制p型载流子浓度和霍尔迁移率，在CuI的掺杂和合金化方面具有高度灵活性，并且提供没有旋转畴的单晶膜。基于CuI的电子器件的演示得到以下努力的支持：（a）通过探索第一成核阶段和各种掺杂剂，（B）通过开发覆盖层以进一步增强CuI的电稳定性，以及（c）通过剥离用于大面积CuI单晶的独立CuI模板。完整的器件异质结构与个人在原位结构的荫罩将实现与项目P05。

Based on the surprisingly promising results in the first funding period, the project work at Universität Leipzig will now focus exclusively on pulsed laser deposition (PLD) of CuI-based heterostructures. However, the portfolio of state-of-the-art microstructural analysis techniques at Fraunhofer IMWS in Halle is not only limited to PLD-grown films, but is used for characterization of all types of CuI samples within the frame of the whole Research Unit. In this way, different growth methods can be compared, for example with respect to adhesion properties of CuI films. In addition to electron microscopical methods, delivering superior lateral resolution (TEM), yet as well rather large screening areas (SEM, EBSD), surface analysis including ToF-SIMS and nanoindentation will be applied. Thereby, the latter represents a promising technique for mechanical characterization. PLD allows to control the p-type carrier concentration and Hall mobility, is highly flexible in doping and alloying of CuI, and provides single-crystalline films without rotation domains. The demonstration of CuI-based electronic devices is supported by the following efforts: (a) by exploring the first nucleation stages and various dopants, (b) by developing capping layers to further enhance the electrical stability of CuI, and (c) by lift-off of free-standing CuI templates for large-area CuI single crystals. Complete device heterostructures with individual in-situ structuring by shadow masks will be realized together with project P05.