Growth of single crystals of different P-type semiconductors, characterization and investigation of their effect on the performance of organic solar cells

Structural design is the key parameter to improve the electrical properties of organic semiconductor electronics. Growth of highly ordered organic crystal is the key to achieving greater charge carrier mobility and longer exciton diffusion length for advanced organic device such as field effect transistors or solar cells. Compared to thin films, organic single crystals are highly ordered and free from disorders. This study includes researches that are among the new methods in solar energy, which is one of the prominent topics in the field of renewable energy, the growth of single crystals of organic semiconductors and their applicationsin double layer solar cells. Highlights the growth of organic materials such as single crystals, their application to the solar cell, the characterization and efficiency of materials. In this study, we aimed to grow desired size and high-quality rubrene, pentacene and tetracene single crystals by physical vapour transport (PVT) under different inert gas flow rate. This method is easy control to get single crystals with desired properties. The single crystals obtained were used on top of the PCBM thin films to fabricate bilayer organic solar cells. The produced single crystals and solar cells characterized by optical microscope, X-ray diffraction (XRD), UV-Visible spectroscopy, atomic force microscope (AFM), and scanning electron microscope (SEM) techniques and solar simulator. Different inert gas flow rate is used as an organic semiconductor parameter. The highest energy conversion efficiency (EDV) of solar cells produced with rubren, pentasen, tetrasen and anthracene single crystals were measured as 0.31%, 0.0197%, 0.0151% and 0.344% respectively.