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Grazing-incidence X-ray scattering (GIXS) formulas for hexagonally perforated layer (HPL) structures withABCandABstacking sequences were derived, and used in the quantitative analysis of the two-dimensional GIXS patterns of polystyrene-b-polyisoprene (PS-b-PI) diblock copolymer thin films supported on silicon substrates. This quantitative analysis provided detailed information (shape, size and size distribution, packing order, layer packing sequence, and orientation) about the HPL structure of the diblock copolymer films that cannot be easily obtained with conventional X-ray and neutron scattering techniques or with conventional microscopic methods.

In this study, a grazing-incidence X-ray scattering (GIXS) formula was derived for gyroid structures formed in thin films supported on substrates. Two-dimensional GIXS patterns were measured for gyroid structures formed in polystyrene-b-polyisoprene (PS-b-PI) diblock copolymer nanometre-scale thin films supported on silicon substrates, and a quantitative analysis of the obtained two-dimensional GIXS data was conducted with the scattering formula. This analysis provided details (lattice parameter, width of the PS phase, positional distortion factor, orientation and orientation distribution) of the gyroid structures developed in the diblock copolymer thin films that are not easily obtained using conventional techniques. Moreover, it was possible to simulate complete and detailed two-dimensional GIXS patterns with the determined structure parameters.

The electron density map of a block copolymer thin film having the hexagonally perforated layer (HPL) structure was directly obtained from the measured grazing-incidence small-angle X-ray scattering (GISAXS) pattern, exploiting the multiple-scattering phenomena present in GISAXS. It is shown that GISAXS is in principle equivalent to three-beam diffraction, which has been used to extract phases of diffraction peaks. In addition, X-ray reflectivity analysis has been performed which, when combined with the GISAXS results, provides full details of the HPL structure.

The mechanism of thermal pore generation in organosilicate thin films loaded with a six-armed star-shaped poly(e-caprolactone) porogen was quantitatively investigated by using in-situ grazing-incidence small-angle X-ray scattering and thermogravimetry. These analyses found that the blend components have a limited miscibility that depends on the composition; for porogen loadings up to only 20 wt%, molecularly miscible blend films were obtained. Even for the miscible blend films, heating the films produced a curing reaction of the precursor matrix component, leading to the phase separation of the porogen component. This phase separation was found to begin at 393 K for 10 wt% porogen loaded films and at 373 K for 20 wt% porogen loaded films, and to continue for temperatures up to 423 K. The porogen aggregates remained and were confined within the matrix film without any further growth or movement until complete thermal decomposition above 564 K.