Pulsed laser ablation of Nd and Pr carbides

In this work, we have evaporated neodymium and praseodymium carbides by a doubled Nd:YAG laser and we have studied the ablation plume by time-of-flight (TOF) mass spectrometry, intensified charge coupled device (ICCD) imaging and emission spectroscopy. The results show that in the gas phase the produced clusters have mainly the (MC2)(n) (where M is the metal) stoichiometry, irrespective of the characteristics of the starting material (pure carbide or mixed metal oxide-graphite powders), while the velocities of neutral and ions seem to be quite low with similar values for all considered particles. The overall data seem to indicate a process in which gas phase reactions play a pre-eminent role. Preliminary results on the deposited films, obtained from X-ray diffractometry (XRD Siemens D5000), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy, indicate that the films are amorphous in structure and their stoichiometry is very close to MC2.