Deposition of Tetracene on GaSe Passivated Si(111)

Abstract

The growth of tetracene on GaSe half-sheet passivated Si(111) is investigated under ultrahigh vacuum (UHV) using low-energy electron diffraction (LEED) and photoelectron spectroscopy (PS). A highly ordered thin-film growth was observed in the initial stages of the deposition process. All proposed structures form a coincidence lattice with the underlying substrate, due to the influence of the molecule-substrate interactions and are built up by either flat lying tetracene molecules at low coverage or tilted molecules at higher coverages. Photoelectron spectroscopy (XPS/UPS) shows that the deposited tetracene molecules induce band bending in the silicon substrate. No band bending was observed in the tetracene film, and an interface dipole potential of 0.45 eV was measured between the GaSe passivated Si(111) surface and the tetracene film.