Growth and annealing kinetics of α‐sexithiophene and fullerene C60 mixed films. Issue 4 (20th July 2016)

• Record Type: Journal Article
• Authors: Lorch, Christopher; Broch, Katharina; Belova, Valentina; Duva, Giuliano; Hinderhofer, Alexander; Gerlach, Alexander; Jankowski, Maciej; Schreiber, Frank
• Is Part Of: Journal of applied crystallography. Volume 49:Issue 4(2016)
• Page Start: 1266
• Page End: 1275
• Publication Date: 2016-07-20
• Subjects: fullerene -- sexithiophene -- real‐time studies -- annealing -- thin‐film growth; Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576716009936
• Languages: English
• ISSNs: 0021-8898

Abstract

Abstract : This is a real‐time in situ study of the growth and annealing of mixtures of the organic semiconductors α‐sexithiophene (6T) and C60 . Interesting crystal‐phase behaviour for different growth conditions and phase transformations during annealing are reported. Abstract : Thin films of α‐sexithiophene (6T) and C60 mixtures deposited on nSiO substrates at 303 and 373 K were investigated in real time and in situ during the film growth using X‐ray diffraction. The mixtures are observed to contain the well known 6T low‐temperature crystal phase and the β phase, which usually coexist in pure 6T films. The addition of C60 modifies the structure to almost purely β‐phase‐dominated films if the substrate is at 303 K. In contrast, at 373 K the low‐temperature crystal phase of 6T dominates the film growth of the mixtures. Post‐growth annealing experiments up to 373 K on equimolar mixtures and pure 6T films were also performed and followed in real time with X‐ray diffraction. Annealing of pure 6T films results in a strong increase of film ordering, whereas annealing of equimolar 6T:C60 mixed films does not induce any significant changes in the film structure. These results lend further support to theories about the important influence of C60 on the growth behaviour and structure formation process of 6T in mixtures of the two materials.