| Abstract [eng] |
The dissertation “Direct Impact of Hot Carriers in Photovoltaics” investigates the role of hot carriers in carrier transport processes in semiconductor photovoltaic devices. The relevance of this research is determined by fundamental efficiency limits of solar cells, particularly energy losses related to hot carrier effects. The aim is to identify the mechanisms of hot carrier formation and their influence on the photoelectric properties of p-n junctions and heterostructures, as well as to assess their potential for improving conversion efficiency of solar cells. Photocurrent formation via intraband and interband absorption in silicon and gallium arsenide structures was investigated across a range of wavelengths and temperatures. It is shown that hot carriers contribute to photocurrent under both above- and below-bandgap excitation, with a strong dependence on radiation intensity and applied voltage. At operating voltages close to the maximum power point, hot carrier effects may introduce additional efficiency losses in p-n solar cells. The carrier temperature is estimated from electrical measurements, providing a practical means to quantify hot carrier dynamics in photovoltaic devices. The novelty of this work lies in demonstrating the universal importance of hot carriers in photovoltaic devices. From a practical perspective, it opens the way for optimizing solar cells and developing advanced photodetectors based on hot carrier effects. On this basis, a new concept of a laser light sensor is proposed. |
