FLEXIBLE BIFACIAL THIN FILM SOLAR CELLS PRODUCED BY PVD/ALD METHODS CONTAINING QUANTUM DOTS

The main objective of the project is to develop an innovative technology for deposition and surface modification of thin films and electrical contacts of flexible bifacial thin-film silicon solar cells in the context of improving their efficiency with high potential for implementation. A flexible silicon solar cell will be built layer by layer on the various and flexible substrates (including glass, metal and polymer foils), which will constitute a part of the structure. The seemingly simple concept requires a series of optimization and specialist research as well as the appropriate selection of individual components from which the solar cell will be built. It is also important to choose the appropriate technique for deposition of individual elements of the solar cell, therefore it is proposed to create active layers and electrical contacts using the magnetron sputtering method, which does not require the use of high temperature, thanks to which it will be possible to use not only metal but also polymer foils as substrates. This method, already well known, is easy to use, scalable and additionally cost-effective. In addition, it is envisaged to use the method of atomic layer deposition (which allows for thickness control at the nanometric level, as well as obtaining the desired optical and electrical properties) for the deposition of a passivation, antireflection thin film and TCO. The main goal of the planned research is to develop a technology for the deposition of P-type silicon base layers, N-type silicon base layer, electrical contacts and functional layers using vacuum methods, as well as the development of a technology for depositing a absorption layer composed of quantum dots by dip coating and spray coating method. The solutions proposed as part of the project are aimed at increasing carrier mobility and lifetime, minimizing optical and electrical losses occurring in a typical solar cell, e.g. by reducing the light reflection coefficient from the front surface of the solar cell, reducing the resistance at the interface semiconductor - front electrode, as well as increasing the quantum efficiency. This type of treatment should make it possible to achieve high photoelectric conversion efficiency.