Depth profiles of ceramic tiles by using orthogonal double-pulse laser induced breakdown spectrometry

The potential of a double pulse (DP) excitation scheme for in-depth characterization of ceramic samples using laser induced breakdown spectrometry (LIBS) has been demonstrated. For this purpose, two Q-switched Nd:YAG lasers in orthogonal configuration were employed, the first one to ablate the sample (1064 nm) and the second one (532 nm) to excite the ablated material. Light emission was collected by a spectrograph and detected by an intensified charge-coupled device (CCD) detector. Optimal conditions such as relative laser beam positions, laser pulse energies, inter-pulse separation and CCD delay time were studied. Depth profiles were evaluated on the basis of various elemental compositions in both layers of ceramic samples. The depth resolution with DIP configuration was improved by almost twofold as compared to the single-pulse approach. The reproducibility of the depth profiles is also twice better with double pulse LIBS. Copyright (C) 2009 John Wiley & Sons, Ltd.