The structural ordering in as-spun and rubbed (then annealed) thin films of poly [(3 -hexylmethoxy)thiophene] has been investigated by means of grazing incidence X-ray diffraction (GIXRD) and the results have been compared with the structural data as obtained from XRD on powder samples. In the structure of the as-spun films the thiophene rings in the backbone lie parallel to the plane of the interface with a well-defined separation among the chains of 19 Angstrom. Rubbing the films creates a unique direction in which the domain size is increased, whereas ordering normal to the rubbing direction is greatly diminished, leading to dichroic behavior. Annealing the films at 95degreesC seems to have no significant effect on the ordering thereafter. (C) 2004 Elsevier Ltd. All rights reserved.