Morphology and Thermal Properties of Semi-Crystalline Polymer Films by Slow Deposition

Thin-film growth viaphysical vapor deposition (PVD) has been successfully exploited for the delicate control of film structure for molecular and atomic systems. The application of such a high-energetic process for polymeric film growth has been an enduring challenge. However, the recent development of Matrix Assisted Pulsed Laser Evaporation (MAPLE) has provided a new means to deposit a variety of macromolecules in a manner similar to PVD. Here, employing MAPLE for the growth of semi-crystalline polymer thin films, we show the ability to tune film morphology by manipulation of substrate temperature. This is accomplished by exploiting the effects of temperature on polymer crystal nucleation and dynamics. During slow film growth, crystal nucleation can either be permitted or suppressed, and crystal thickness can be tuned by temperature modulation. Finally, by combining MAPLE deposition with flash DSC, we demonstrate the ability to measure the extent of crystallinity and melting temperature of thin films grown over a wide temperature range.