Energy Level Bending in Ultrathin Polymer Layers Obtained through LangmuirShfer Deposition

1077 wileyonlinelibrary.com © 2015 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim polycrystalline and defects/variations in the local order of OSC fi lm create a distribution of ionization energies. [ 1 ] Every molecule/polymer in a fi lm will thus have its own individual ionization potential (IP) and electron affi nity (EA), with the fi lm IP and EA then represented by the smallest/ largest individual IP/EA. The frontier parts of the resulting occupied and unoccupied state distributions forming the energy gap are often modeled as being either Gaussian or exponential, [ 2 ] and the most easily oxidized/reduced states in an OSC fi lm are typically referred to as tail states or gap states. [ 3 ] Due to processing conditions relevant to printed electronics, the fi lms typically are physisorbed on substrates, forming weakly interacting interfaces. The energy level alignment at interfaces [ 3–7 ] and over heterolayer stacks [ 8 ]