Substrate-induced phase of a [1]benzothieno[3,2-b]benzothiophene derivative and phase evolution by aging and solvent vapor annealing

Andrew O. F. Jones, Yves H. Geerts, Jolanta Karpinska, Alan R. Kennedy, Roland Resel, Christian Röthel, Christian Ruzié, Oliver Werzer, Michele Sferrazza

Research output: Contribution to journalArticlepeer-review

38 Citations (Scopus)
136 Downloads (Pure)


Substrate-induced phases (SIPs) are polymorphic phases that are found in thin films of a material and are different from the single crystal or "bulk" structure of a material. In this work, we investigate the presence of a SIP in the family of [1]benzothieno[3,2-b]benzothiophene (BTBT) organic semiconductors and the effect of aging and solvent vapor annealing on the film structure. Through extensive X-ray structural investigations of spin coated films, we find a SIP with a significantly different structure to that found in single crystals of the same material forms; the SIP has a herringbone motif while single crystals display layered π-π stacking. Over time, the structure of the film is found to slowly convert to the single crystal structure. Solvent vapor annealing initiates the same structural evolution process but at a greatly increased rate, and near complete conversion can be achieved in a short period of time. As properties such as charge transport capability are determined by the molecular structure, this work highlights the importance of understanding and controlling the structure of organic semiconductor films and presents a simple method to control the film structure by solvent vapor annealing.

Original languageEnglish
Pages (from-to)1868-1873
Number of pages6
JournalACS Applied Materials and Interfaces
Issue number3
Early online date8 Jan 2015
Publication statusPublished - 28 Jan 2015


  • organic electronics
  • x-ray diffraction
  • substrate-induced phase
  • polymorphism
  • organic thin films


Dive into the research topics of 'Substrate-induced phase of a [1]benzothieno[3,2-b]benzothiophene derivative and phase evolution by aging and solvent vapor annealing'. Together they form a unique fingerprint.

Cite this