Indexed by:期刊论文

Date of Publication:2018-06-01

Journal:SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY

Included Journals:SCIE、EI、Scopus

Volume:144

Page Number:38-45

ISSN No.:0584-8547

Key Words:Laser-induced ablation; Quadrupole mass spectrometry; Laser-induced breakdown spectroscopy; Thin film solar cell; Preparation-free sample analysis

Abstract:Monitoring a sample's material composition became more and more important over the last years for both - industrial process control as well as for post mortem analysis in research and industrial development. Although material composition identification as well as a comparison with standard samples works fine, there is a lack of diagnostics which can provide quantitative information with depth resolution without any standard samples. We present a novel method utilizing a residual gas analysis with quadrupole mass spectrometry after picosecond laser-induced ablation and release of volatile species. In the present experiment, well characterized multilayer thin film solar cells (mu c-Si:H and a-Si:D as p-i-n-junctions on ZnO:Al electrodes) are used as a set of well characterized material samples to demonstrate the capabilities of the new method.
   The linearity of the spectrometer signal to gas pressure simplifies its calibration and reduces its uncertainties in comparison with other analysis techniques, although high vacuum conditions (10(-6) hPa to 10(-7) hPa) are required to reach high sensitivity better than the percent-range. Moreover, the laser-ablation based sample analysis requires no preparation of the sample and is flexible regarding ablation rates. The application of a picosecond laser pulse ensures that the thermal penetration depth of the laser is in the same order of magnitude as the ablation rate, which enables to achieve depth resolutions in the order of 100 nm and avoids matrix mixing effects at the edge of the laser -induced crater in the sample. (C) 2018 Elsevier B.V. All rights reserved.