Direct melt processing of pentacene at temperatures above 1000 °c by pulsed laser irradiation

Pentacene remains as a leading candidate for organic thin film transistors in applications such as sensor and flexible displays. Its processing, however, has been limited to relatively low temperatures and only in the solid phase. Liquid pentacene has never been experimentally observed, although the melting temperature is predicted to lie between 200 and 400 °C. We report a method of heating pentacene thin films to temperatures above 1000 °C using pulsed laser irradiation. This rapid heating induces morphological changes consistent with formation of a transient liquid phase. X-ray diffraction and Raman spectroscopy show that the pentacene remains intact after processing at these extreme temperatures.