An X-ray scanner comprises an array of X-ray detectors arranged in cylindrical configuration around an imaging volume, and a multi-focus X-ray source which extends in a helical configuration around the outside of the detector array. The segmented squeegee may include a plurality of independent squeegee segments or elements, a support structure and a plurality of independent connections or linkages connecting the squeegee segments to the support structure. Insulating lines define a width of the buried contact.