Surface Modification via Atomic Layer Deposition

原子层沉积（ALD）是一种薄膜技术，很大程度上归功于化学气相沉积（CVD），但它提供了生长薄膜的原子水平控制，因此为沉积复杂的层状薄膜提供了独特的机会。沉积的薄膜没有针孔，至关重要的是，具有低缺陷密度，而固有的100%薄膜密度为给定材料提供了接近“理想”的性能。ALD是一种可用于表面改性的技术，与CVD相比，它具有低温技术的优点。该项目的目的是研究使用ALD来修饰表面，以调整表面的亲疏水性（金属氧化物或聚合物）。ALD将用于修饰表面，如氧化物，通过改变沉积模式从热增强到等离子体增强，使其成为疏水性或亲水性。疏水性是一系列应用的关键表面特性，在这些应用中，水吸附会降低性能，例如微机电系统（mems）上的保护涂层或聚合物基板上的气体扩散阻挡层。要将表面（如金属氧化物）从亲水性变为疏水性，通常需要使用对环境有害的氟化聚合物。利用ALD，拟议的项目将利用沉积温度低和表面易于改性的优势，在聚合物上实现涂层，例如用于防滑PVC安全地板和卫生PVC墙覆层的聚合物。这种组合可以创造一种创新的“易于清洁”的涂层，用于防滑地板和卫生的PVC墙覆层。这将与EPSRC的医疗保健和制造技术主题领域联系起来。ald沉积在PVC上的金属氧化物膜也将作为PVC和环境之间的有效钝化层。这可以扩展到其他应用，如太阳能电池涂层。

Atomic Layer Deposition (ALD) is a thin-film technique that owes much to Chemical Vapour Deposition (CVD), but provides for atomic level control of the growing film and therefore unique opportunities for depositing complex and layered thin-films. The deposited films are pinhole free and, crucially, have a low defect density, whilst the inherent 100% film density provides near 'ideal' properties for a given material. ALD is a technique that can be used for surface modification and has the advantage that it is a low temperature technique in contrast to CVD. The aim of this project is to investigate the use of ALD to modify surfaces in order to tune the surface's hydrophilic/hydrophobic property (metal oxides or polymers). ALD will be used to modify surfaces, such as oxides, to be either hydrophobic or hydrophilic by changing deposition mode from thermal to plasma-enhanced. Hydrophobicity is a key surface property for a range of applications, where water adsorption can deteriorate the performance such as for protective coatings on microelectromechanical systems (MEMSs) or gas diffusion barrier layers on polymer substrates. To alter a surface, such as a metal oxide, from hydrophilic to hydrophobic, typically requires the use of fluorinated polymers, which are harmful to the environment. Using ALD, the proposed project will take advantage of the low temperature of deposition and the ease of modification of the surface to achieve coatings on polymers, such as those utilised in slip resistant PVC safety flooring and hygienic PVC wall cladding. Together this combination could create an innovative new 'easy-to-clean' coating for slip-resistant flooring and hygienic PVC wall cladding. This will link in with healthcare and manufacturing technologies theme area of the EPSRC. The ALD-deposited metal oxide films on PVC would also act as an effective passivation layer between the PVC and the environment. This could then be expanded into other applications such as in coatings for solar cells.