Preparation of self-ordered molecular layers by pulse injection

We have used the pulse injection technique for the preparation of ordered molecular layers of Cu-TBPP molecules, avoiding any heating procedure of the molecules for their deposition. The controlled removal of the pure solvent is characterized by thermal desorption spectroscopy and is proved by the observation of large areas of clean self-ordered molecular layers by scanning tunnelling microscopy at 8 K after pulse injection and subsequent annealing. A comparison with results obtained by conventional deposition by sublimation reveals an equivalent appearance of the molecules, which is dominated by the lateral phenyl groups. The molecular structure of the Cu-TBPP layer is characterized and different domains are found which show the influence of the copper substrate on the growth orientation.