Organic semiconductors have attracted attention due to their application in solar cells, field effect transistors, light emitting diodes and sensors. Polymeric semiconductors are a subset of organic semiconductors and are typically deposited by solution based methods. The solution processed methods which are suitable for large area deposition, such as printing or slot die coating, leads to inferior morphology of the polymer films and affects the performance of the optoelectronic devices. In this work, we demonstrate chemical vapor deposition (CVD) as an alternate method of polymer deposition and device fabrication. Film deposition by CVD has the advantage that up-scaling for deposition on large area substrates is possible without compromising on the electrical/morphological properties. In seminar 1, a study of organic field effect transistors with CVD grown poly (p-phenylenevinylene) (PPV) as the active material was presented. It was shown that the hole mobility is 100 times higher than that of spin coated PPV films. In this seminar, a study of UV-blue photodiodes with CVD grown PPV as the active material is presented. High efficiency is achieved by optimizing the device structure using transfer matrix simulations for maximizing the optical electric field distribution. A comparison between the photodiodes of CVD grown PPV with spin coated PPV shows that growth by CVD results in significant improvement in responsivity. The high responsivity is attributed to the optimized device geometry and enhanced hole mobility in CVD grown PPV. The spectral response of CVD grown PPV UV-blue photodiode is comparable or higher than other organic and inorganic UV-blue photodiodes operating under low bias condition. A modified CVD system for deposition of the polymer poly (p-phenylene) (PPP) is demonstrated. The influence of charge transport layers on the performance of organic light emitting diodes with CVD grown PPV and PPP films as emissive layer is presented.