Thin Film Deposition
During the production of thin-film solar panels, several layers are deposited on a substrate made of glass, metal, or a flexible synthetic material. There are many different ways to apply the layers. Our research is focused on finding a fast (and therefore inexpensive) deposition process, combined with achieving a high quality end product with a high yield.
Protecting the top layer during the deposition process
Solliance has a new pilot production line, which can manufacture PV foils roll-to-roll via a wet chemical moulding process. (The alternative is ‘sheet-to-sheet’, which isn’t a continuous process, but one where units are passed through the machine piece by piece.) In its outward appearance, this roll-to-roll process resembles a printing press.
The machine is designed to apply extremely thin and homogeneous layers. The foils are transported along ‘deposition drums’, which are large rolls which deposit layers on the substrate. To prevent the upper layers from becoming damaged, the process is designed so that the foils ‘float’ over the drum. As a result, physical contact with the deposited layers is avoided.
No contamination or damage
The different layers must not only be applied uniformly, but also very carefully. We therefore designed processes such that not only is direct physical contact avoided with the deposited layer, but deposition usually also takes place in a clean room. As a result, there will only be minimal contamination of the layers during the production process.
Another way to deposit quickly and carefully is the spatial ALD technique, where atomic layers are applied at a very high speed. By using ALD, the layers are of the same thickness across the entire surface, and perfectly matched, allowing for an optimal transfer of electricity. We have developed machines for both sheet-to-sheet and roll-to-roll ALD deposition.
Cheaper production at lower temperatures and at atmospheric pressure
Producing at low temperatures contributes to a substantial cost reduction. Not only does it ensure lower energy consumption, but it also makes it possible to use cheap plastic substrates (which would melt at high temperatures). We have developed a deposition process which does not require a vacuum. This makes the process cheaper.
Some materials in common PV modules are toxic. We are doing research on new processes and material choices that reduce toxicity.
The market demands customisation, instead of solar panels in standard dimensions. It should be possible to tailor panel dimensions to your particular application, which would allow you to integrate solar panels in your products in different ways. This could take the form of, for example, roof covering PV systems, or foils laminated on car roofs.
Customisation or tailor-made solutions call for an innovative production process. Adjacent cells in a panel must be electrically interconnected. Traditionally, this takes place in between the various deposition steps. Solliance is working on a back end interconnection technology, where deposition takes place first, which is then followed by interconnection. This allows large-scale production of semi-finished products, which are only customised in the final stage.
Integration of flexible solar panels in existing products, for application in, for example, the construction or auto industry, is the future. However, this will require more than customisation alone. It will also be necessary to examine what the best way is to integrate solar panels into products quickly and on a large scale. An important question is at which stage in the production process this should happen. Another question is how to ensure that the solar panels are not visible in the final product, and yet provide sufficient yield.
Lifetime testing and modelling
Solliance has a unique device in-house for accelerated testing of the lifespan of thin-film solar panels. The system is unique because the climate chamber is equipped with an artificial sun, which allows us to also measure the effect of sunlight. The system also allows us to investigate the influence of extreme temperatures and moisture, or break the panels in a controlled manner to see what happens exactly. Valuable information can be obtained from a simulated accelerated ageing process. For example, information about which materials are sensitive to particular influences, or which layers break and how. This information is then used as input for further research into the improvement of the performance of different types of panels.
Do you see business opportunities in the application of the latest generation of solar cells? Do you see opportunities for your company or relating to the creation of a new business? If so, Solliance can perform a feasibility study for you. Not only do we keep abreast of all of the latest PV technologies, but we also know the market inside and out.
Innovative technologies are only promising if they result in cost efficient production. This will depend on many factors. For example, the cost of materials or manufacturing processes could play an important role here, or the expected energy output or lifespan of the solar panels or semi-finished products. Solliance can make a detailed cost calculation for you by comparing the various relevant factors, which will show you if your innovation is worth investing in.
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