Fig. 2.
Energy diagrams. Carrier injection mechanism of a metal electrode of Schottky limit and b new electrode consisting of a bilayer (polycrystalline organic semiconductor (pc-OSC)/tetratetracontane (TTC) covered by a metal thin film (Au, Ca etc.) for FETs of single-crystalline OSC (sc-OSC). From left to right: separated metal and semiconductor, contacted metal and semiconductor, electron injection, and hole injection. c Fermi level (E F) of Ca and Au, HOMO and LUMO of rubrene (RU) and 5,5′-di(4-biphenylyl)-2,2′-bithiophene (BP2T)