Chemical analysis of thin films by means of SS-MS, GD-OES, and XPS demonstrated at Ir-Si thermoelectrica

Analytical methods with low detection limits were used for the investigation of Ir-Si thin films, the physical properties of which vary strongly with the chemical composition and the amount of impurities. It is demonstrated how to solve chemical characterization of different thermoelectric Ir-Si thin films by spark source mass spectrometry (SS-MS), glow discharge optical emission spectroscopy (GD-OES) and X-ray photoelectron spectroscopy (XPS). The combined use of the three different facilities allows the quantification of impurities of elements of the entire periodic system in the ppm range (down to 30 at.-ppm in dependence on the element) incorporated in thin film samples. Additional information about the in-depth distribution of elements or specifically bonded species can be achieved with a high depth resolution. Received: 6 April 1998 / Revised: 9 July 1998 / Accepted: 14 July 1998