A novel two-dimensional organic semiconductor material [1]benzothieno[3,2-b][1]benzothieno[2,1-b:3,4-b':6,5-b'':7,8-b''']tetra(benzothiophene) (BTBTTBT) which largely extends the scope of the π-conjugated framework of heteroarene through "H" configuration was synthesized and its thermal, optical and electrochemical properties were investigated. This 2D molecule enables the easy growth of single-crystalline microribbons by the physical vapor transport method, which were evidenced by XRD, SEM and TEM. The single-crystalline OFET devices were fabricated based on the individual BTBTTBT microribbon and the remarkable high mobility of 17.9 cm(2) V(-1) s(-1) and on/off ratios of over 10(7) could be achieved.