| The use of organic semiconductors in electronic devices emerged with the fabrication of photovoltaic cells with organic dyes and in recent years their applications have extended to field effect transistors (FETs) and light emitting devices (LEDs). Increased attention towards organic semiconductors and materials is mainly due to flexibility they provide with respect to the properties of individual molecules and fabrication in desired shapes.; Among n-type semiconductors, perylenetetracaboxylicdiimide (PTCDI), is gaining increasing attention due to its high photo and thermal stability. With the modification of side chains with different functionalities, one can tune the solubility of molecule in different solvent and the morphology of resultant molecular aggregates.; Following work presents the use of PTCDI molecules with three different side chains attached to PTCDI core. We investigated the effect of different side chains on resultant morphology when fabricated through different processing techniques. Fabrication techniques applied are solution based processing and surface assisted solvent vapor annealing. The later technique provides a better control over the size and shape of resultant nanocrystals.; We investigated the size and optical properties of nanocrystals formed with the help of atomic force microscopy (AFM) and near-field scanning optical microscopy (NSOM).; Through solution based and surface assisted solvent vapor annealing processes under different conditions, we have fabricated nanocrystals with different aspect ratios, size and shape. Currently we are working on investigation of electrical measurements for application of nanocrystals in real time electronic devices. |
