A novel semiconductor based on annelated beta-trithiophenes is presented, possessing an extraordinary compressed packing mode combining edge-to, face pi-pi interactions and S ... S interactions in single crystals, which is favorable for more effective charge transporting. Accordingly, the device incorporating this semiconductor shows remarkably high charge carrier mobility, as high as 0.89 cm(2) V-1 s(-1), and an on/off ratio of 4.6 x 10(7) for vacuum-deposited thin films.