Remote Plasma Sputtering of High Quality Thin Films for Advanced Functional Applications and Devices

等离子体探索有限公司(PQL)开发了一种获得专利的远程等离子溅射技术，该技术可以沉积高质量、均匀的薄膜。由于等离子体是从溅射靶远程产生的，因此由于离子密度和靶偏压的独立控制，它比其他传统的溅射技术更具优势。这允许更宽的溅射参数空间用于高速沉积现有的和新的或复杂的材料及其相关的薄膜特性。尽管与其他技术相比，这项新技术已经具有许多已知的优点，但PQL仍在不断努力加深对等离子体、溅射焊剂和薄膜涂层复杂且相互关联的动力学和特性的了解，以期提供更强的涂层能力。最近MinMaT EngD显示，很大一部分溅射通量被高密度等离子体连续电离。该工艺固有的电离物理气相沉积(IPVD)特性与衬底偏置相结合，可用于控制电离溅射通量的能量和方向。因此，可实现更广泛的薄膜性能，并能够通过重新溅射过程对复杂结构进行共形涂层，包括悬垂结构的底面。拟议的EngD所涉及的工作将集中于更深入地了解等离子体、溅射通量和薄膜性能之间的关系，以潜在地增强该技术的所有方面，从而成功实现商业化。这将包括制定保形覆盖沉积程序。由于使用远程等离子溅射的过程仍处于初级阶段，PQL需要对如何在商业层面上成功实施达成更基本的理解。另一个研究领域将是优化技术规模--从研发到工业规模。对于商业化来说，最大限度地提高溅射通量传递系数和沉积速率，同时仍能在较大面积上以最小的能耗和单位面积成本保持所需的薄膜性能，对系统购买者来说尤为关键。对于这两个研究领域，等离子体、溅射通量和薄膜性能之间的相互关系可以通过系统地改变i)等离子体条件；ii)沉积参数；iii)沉积各种薄膜材料来实现。感兴趣的材料包括但不限于VO2，因为它的热致变色特性，以前使用PQL技术进行的研究表明，可以修改相变温度，以及Al2O3的介电击穿特性。其他一般材料包括透明导电氧化物和介电材料。该大学提供的表征涂层性能的技术包括形貌的扫描电子显微镜，成分的EDX，拉曼和XPS，结构的X射线衍射仪，表面粗糙度的原子力显微镜。PQL提供用于等离子体和溅射通量分析的OES，以及UV-VIS-NIR光谱、薄膜应力和厚度测量、光学和扫描电子显微镜、EDX和电阻率。根据收集的经验数据，建立一个将沉积系统变量的所有方面与涂层性能联系起来的模型将是非常可取的。

Plasma Quest Ltd (PQL) has developed a patented remote plasma sputtering technology which deposits high quality, uniform thin films. As the plasma is generated remotely from the sputter target it offers advantages over other conventional sputtering techniques due to the independent control of the ion density and target bias. This allows a much wider sputter parameter space for the high rate deposition of both existing and new or complex materials and their associated thin film properties. Although the novel technology already has many known benefits over other technologies, PQL continually strives to deepen its understanding of the complex and interrelated dynamics and properties of the plasma, sputter flux and thin film coatings, with the aim of offering enhanced coating capabilities. A recent MinMaT EngD revealed that a significant fraction of the sputter flux is continuously ionised by the high-density plasma. The inherent ionised physical vapour deposition (iPVD) nature of the process, in conjunction with substrate biasing, can be used to control the energy and direction of the ionised sputter flux. Thus, resulting in an even wider variety of thin film properties achievable and the ability conformally coat complex structures, including the underside of over-hanging structures by the process of re-sputtering. The work involved in the proposed EngD will be focussed on developing a deeper understanding of the relationship between the plasma, sputter flux and thin film properties for potential enhancement of all aspects of the technology for successful commercialisation. This will include the development of the conformal coverage deposition process. As the process, using remote plasma sputtering, is still in its infancy, PQL needs to develop a more fundamental understanding of how it can be successfully implemented on a commercial level. Another area of research will lie in the optimisation of technology scale-up from R&D to industrial size. For commercialisation the maximisation of sputter flux transfer factor and deposition rate, whilst still maintaining the desired thin film properties over large area and at minimal energy consumption and cost per unit area conditions is particularly crucial to system purchasers. For both areas of research, the interrelation between plasma, sputter flux and thin film properties can be achieved by systematic variation of the i) the plasma conditions; ii) deposition parameters; iii) deposition of a variety of thin film materials. Materials of interest include, but are not limited to, VO2 due to its thermochromic properties, with research previously conducted using PQL technology revealing that a modification of the phase transition temperature is possible and Al2O3 for its dielectric breakdown properties. Other general materials include transparent conducting oxides and dielectrics. Techniques available at the University to characterise the coating properties include SEM for morphology, EDX, Raman and XPS for composition, XRD for structure, AFM for surface roughness. OES for plasma and sputter flux analysis is available at PQL, along with UV-VIS-NIR spectroscopy, thin film stress and thickness measurement, optical and scanning electron microscopy, EDX and electrical resistivity. From the empirical data collected the creation of a model relating all aspects of the deposition system variables to coating properties would be highly desirable.