We investigate the heteroepitaxial growth of Bi2Se3 films on FeSe substrates by
low-temperature scanning tunneling microscopy/spectroscopy. The growth of Bi2Se3 on FeSe
proceeds via van der Waals epitaxy with atomically flat morphology. A striped moire pattern ´
originating from the lattice mismatch between Bi2Se3 and FeSe is observed. Tunneling spectra
reveal the spatially inhomogeneous electronic structure of the Bi2Se3 thin films, which can be
ascribed to the charge transfer at the interface.