Morphologies of Pentacene Crystals Obtained by Physical Vapor Growth Technique

Three kinds of morphologies were observed in the pentacene crystals obtained by physical vapor growth, such as the whisker-type morphology, the plateletlike morphology with large parallelogram planes, and the plateletlike morphology with large dendritic planes. Plateletlike crystals have a common basal (001) plane, despite possessing different morphologies, that is, either the parallelogram or dendritic planes. The results of white-beam X-ray diffraction analysis revealed that the crystal qualities depended on the growth condition rather than on the crystal morphology.