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

Plasma Quest有限公司（PQL）开发了一种获得专利的远程等离子体溅射技术，可沉积高质量、均匀的薄膜。由于等离子体是在远离溅射靶的地方产生的，因此由于离子密度和靶偏压的独立控制，其提供了优于其他常规溅射技术的优点。这允许更宽的溅射参数空间，用于现有和新的或复杂材料的高速率沉积及其相关的薄膜性质。虽然这项新技术已经比其他技术具有许多已知的优势，但PQL仍在不断努力加深对等离子体、溅射焊剂和薄膜涂层的复杂和相互关联的动力学和性质的理解，旨在提供增强的涂层能力。最近的MinMaT EngD显示，溅射通量的很大一部分被高密度等离子体持续电离。该工艺的固有电离物理气相沉积（iPVD）性质结合衬底偏压可用于控制电离溅射通量的能量和方向。因此，导致可实现的甚至更宽种类的薄膜性质以及通过再溅射工艺保形地涂覆复杂结构（包括悬垂结构的下侧）的能力。参与拟议工程设计的工作将侧重于深入了解等离子体、溅射通量和薄膜特性之间的关系，以潜在地增强该技术的各个方面，从而成功实现商业化。这将包括保形覆盖沉积工艺的发展。由于使用远程等离子体溅射的工艺仍处于起步阶段，PQL需要对如何在商业层面上成功实施有更基本的了解。另一个研究领域将是优化从研发到工业规模的技术规模。对于商业化而言，溅射通量转移因子和沉积速率的最大化，同时仍然在大面积上保持所需的薄膜性质，并且在每单位面积的最小能耗和成本条件下，对系统购买者来说特别重要。 对于这两个研究领域，等离子体、溅射通量和薄膜性质之间的相互关系可以通过i）等离子体条件; ii）沉积参数; iii）各种薄膜材料的沉积的系统变化来实现。感兴趣的材料包括但不限于VO 2（由于其热致变色特性）和Al 2 O3（由于其介电击穿特性），先前使用PQL技术进行的研究表明，可以修改相变温度。其他一般材料包括透明导电氧化物和氧化物。该大学现有的技术来验证涂层性能，包括SEM的形态，EDX，拉曼和XPS的组成，XRD的结构，AFM的表面粗糙度。PQL提供用于等离子体和溅射通量分析的OES，沿着紫外-可见-近红外光谱、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，非常需要建立一个模型，将沉积系统变量的所有方面与涂层性能联系起来。

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.