The research objective of this research is to develop a measurement method that can measure thin film thicknesses through a multilayer that consists of both surrounding thick layers and in between thin films. An optical non-contact measurement method is researched and developed to non-destructively measure the thickness of a liquid thin film, which is situated between other layers. The measurement method used in this research is called spectral reflectance. The method works by analyzing the reflectance spectrum from a light beam which is directed perpendicularly and with a wide range of wavelengths on the surface of the layer. The reflectance spectrum that is measured with a spectrometer includes oscillations that result from the interference of light that reflects at the different interfaces in the multilayer. The oscillation contains frequency content which is used to determine the thickness of the layer. This research shows that the spectral reflectance technique can be used to measure the thickness of a stack of thin films with the condition that the thin films are all coherent. It is possible to determine the film thickness of a stack coherent thin films, which are surrounded by incoherently thick layers. The outer layers can be assumed to be incoherently thick based on a combination of factors such as the layer thickness of the thick layer, the measured wavelength range and the resolution of the spectrometer.

Silicon wafers and solar cells are delicate components used in the semiconductor industries and energy industries. Handling and transportation can easily damage these components. Conventional handling methods with mechanical contact can cause various damages to these delicate surfaces. Air bearings can provide a solution by enabling an almost frictionless support between two moving surfaces. With air bearings, a pressurised layer of air is present that eliminates mechanical contact. Textures on an air bearing surface can enhance the load capacity and stiffness of the system. In this report, an unconventional manufacturing method for a large, textured air bearing surface is proposed, which is nanoimprinting. Nanoimprinting is a manufacturing technique to pattern micro- and nanoscale textures with UV-curable resin. These textures can enhance the load capacity and stiffness of an air bearing. With nanoimprinting, a master (mould) is required, and from this master, copies are made. By creating a grid of these copies, a cost-effective upscaling step can be carried out. In this project, two functioning textured nanoimprinted air bearing demonstrators were realised. The first demonstrator is a one-to-one copy of the master. For the second demonstrator, an up-scaling step was carried out. Feature depths of 14 μm were realised with nanoimprinting, with a roughness between 1 and 2 μm. Stiffnesses in the air bearing film of 3000 N/m and 550 N/m were accomplished for the first and second demonstrators, respectively.

Nanoimprinting is a manufacturing method to replicate micro- and nanotextures on large-area substrates with ultraviolet-curable resins. Significant potential of large-area nanopatterning lies in its capacity to greatly enhance the performance of an abundance of devices and foster the creation of cutting-edge products. However, current large-area imprinting techniques require improvement in order to achieve high resolution, high throughput and cost-effectiveness, whilst imprinting in a thin uniform resin layer. This work presents the development of a demonstrator to passively control the film thickness in hydrodynamic lubrication on non-flat surfaces in nanoimprinting lithography. Using low stiffness actuation, it was expected that film thickness uniformity increases during imprinting. In this project a functioning demonstrator is realised, where the film height under a slider bearing is passively controlled. The slider bearing behaviour has been tested on various flat and non-flat surfaces. Film heights of 80-160 micrometer were realised on non-flat substrates of 800 micrometer.

Improved handling methods are required in order to decrease the manufacturing cost of solar cells and flat panel display. A potential method would be to use a contactless handling system based on air bearing technology. As the name implies, the substrate levitates on a thin film (~10 μm) of air. The viscous shear force is used to exert a lateral force on the substrate. In order to be able to control the position of the substrate, this force needs to be controlled over time. In this research, this is achieved by varying the film geometry of the outlet. This thin film (~50 μm) is formed between a pin in a slightly oversized hole. The full system is comprised of multiple unit cells, which makes manufacturing using traditional subtractive manufacturing techniques very complicated. During this research, a novel manufacturing method was developed, where the dimensions of the outlet film are relatively insensitive for manufacturing errors.

Roll-to-Plate (R2P) nanoimprint lithography (NIL) is a fabrication process with the potential for low-cost high-volume fabrication of micro- and nano-patterns on large areas. As a result, R2P is regarded as a promising production process for micro- and nano-scale features which exceed the conventional wafer sizes. In addition, the process has the potential to scale up the production of wafer based textures at a low costs, which would make the implementation of nano-features in products more accessible. To compete with alternative fabrication techniques, R2P NIL must meet requirements set by the industry for position accuracy and system repeatability. In this thesis, a study is performed on the positioning of micron- and nano-sized features in a two-dimensional plane in collaboration with Morphotonics, a company based in Veldhoven the Netherlands. The metrology of overlay from the semi-conductor industry is applied to NIL, to quantify the relative displacement and deformations of a given nano-pattern. Experimental results, obtained in a preliminary phase of the project, characterized the current overlay performance of machines available at Morphotonics. From the test results, a positioning error of the complete nano-pattern was found, in combination with a complex deformation which affected the relative distance of the imprinted features. Based on the characterization of overlay in R2P NIL, an interest in deformations of the flexible mould is developed. Concepts from roll-to-roll (R2R) production processes are used, to quantify the deformations observed in experiments. In R2R processes, deformation of a thin elastic material (web) is quantified by applying a beam model to the web. Using the beam model, the deformation of a web segment, constrained by two rollers, could be quantified in both quasi-static and dynamic conditions. The models based on literature of lateral web dynamics, combined with experimental results obtained at Morphotonics, have given insight in the behaviour of the elastic mould during the imprint process. The models describe the transverse motion of the web on a roller surface and the deformation of the web in between two consecutive rollers in a dynamic system. Verification of the model was performed on the machines of Morphotonics. The transverse motion of the elastic mould over the rollers was clearly observed in the measurement, including a repeatable deformation pattern of the imprints as a result of a forced disturbance exposed to the system. Both of which, were expected to be observed based on the modelled expectations. Nevertheless, the exact error magnitude did not meet the expectations and only a rough relation between model and experimental results was found. In spite of the verification results not perfectly matching the model, the theory applied in this thesis has given insight in the behaviour of elastic materials in roller based transport. From the observations and gathered knowledge of this thesis, the performance of overlay in large scale roll-to-plate nanoimprint lithography has been characterized and considerations for future imprint modules have been made.