In order for organic electronic devices to reach their full potential, their structure-function properties must be better understood. A comprehensive model of charge transport has been proposed that accurately describes the behavior of a wide range pi-conjugated materials. This model describes charge transport both within crystallites and between them by accounting for the coulomb repulsion in crystallites occupied by more than one charge carrier. In order to validate this model in thin film transistors, where charge transport takes place almost exclusively within a thin layer at the interface to the dielectric, detailed information about crystalline domains in this charge transport region is required. Using grazing incidence wide angle x-ray scattering (GIWAXS) with varying angle of incidence, we are able to probe crystallites within the first few nanometers of the film. At angles of incidence below the critical angle of the film, impinging x-ray intensity decays exponentially as a function of depth, allowing control over the depth sensitivity of the GIWAXS measurements. Crystalline parameters can then be plotted versus angle of incidence to quantitatively compare the crystalline population at a film’s surface to that in the bulk. This structural characterization will be discussed along with the details of the proposed charge transport model in organic systems.