One advantage of the pulsed laser deposition (PLD) method is the stoichiometric transfer of multicomponent target material to a given substrate. This advantage of the PLD determined the choice to prepare chalcogenide-based thin films with an off-axis geometry PLD. Ag-As-S and Cu-Ag-As-Se-Te targets were used to deposit thin films on Si substrates for an application as a heavy metal sensing device. The films were characterized by means of Rutherford backscattering spectrometry (RBS), transmission electron microscopy (TEM), and electrochemical measurements. The same stoichiometry of the films and the targets was confirmed by RBS measurements. We observed a good long-term stability of more than 60 days and a nearly Nernstian sensitivity towards Pb and Cu, which is comparable to bulk sensors.