In-Situ Observation Of Stacking Fault Evolution In Vacuum-Deposited C-60

We report an in-situ study of stacking fault evolution in C-60 thin films using grazing-incidence x-ray scattering. A Williamson-Hall analysis of the main scattering features during growth of a 15nm film on glass indicates lattice strain as high as 6% in the first 5 nm of the film, with a decrease to 2% beyond 8 nm thickness. Deformation stacking faults along the {220} plane are found to occur with 68% probability and closely linked to the formation of a nanocrystalline powder-like film. Our findings, which capture monolayer-resolution growth, are consistent with previous work on crystalline and powder C-60 films, and provide a crystallographic context for the real-time study of organic semiconductor thin films. (C) 2017 Author(s).