We have studied the growth mode of lead-phthalocyanine sublimated in ultrahigh vacuum conditions over Si(100)-(2 × 1) and Si(111)-(7 × 7) clean substrates. The samples have been studied in situ by means of X-ray photoelectron spectroscopy using non-monochromatized and monochromatized radiation, and also with a combined atomic force microscope (AFM)/scanning tunneling microscopy (STM) instrument. Occasionally their morphology has been also determined in air by means of a tapping-mode AFM. We give strong evidences for a planar adsorption of the shuttle-cock shaped PbPC molecule over the two substrates at the very initial stages of deposition. We report some original results of a combined STM/AFM experiment with measurements showing simultaneously taken height and tip-sample interaction force maps.