Structural Evolution of Cylindrical-Phase Diblock Copolymer Thin Films

We have measured the time evolution of the self-assembly process in perpendicular-oriented cylindrical-phase diblock copolymer thin films using statistical analysis of high-resolution scanning electron microscope (SEM) images. Within minutes of annealing above the polymer glass-transition temperature, microphase separation between polymer blocks results in formation of uniform nanometer-scale domains whose relative position is initially largely uncorrelated. On further annealing, the cylindrical polymer domains organize into a two-dimensional hexagonal lattice whose characteristic grain size increases slowly with time (∼t 1/4). © 2004 Wiley Periodicals. Inc.