| Zugriffsnummer | 21147 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Reference-free TXRF analysis of semiconductor surfaces with synchrotron radiation |
| Autor(in); Institution |
Beckhoff, Burkhard; 7.1, Photonenradiometrie, PTB-Berlin
Fliegauf, Rolf; 7.1, Photonenradiometrie, PTB-Berlin
Kolbe, Michael; 7.1, Photonenradiometrie, PTB-Berlin
Müller, Matthias; 7.1, Photonenradiometrie, PTB-Berlin
Weser, Jan; 7.1, Photonenradiometrie, PTB-Berlin
Ulm, Gerhard; 7.1, Photonenradiometrie, PTB-Berlin
|
| Quelle/Jahr | Analytical Chemistry: 79 (2007), 20, 7873 - 7882 |
| ISSN | 0003-2700 (PRINT) ; 1520-6882 (ONLINE) |
| DOI | |
| Verlag | Washington, DC: Soc. |
| Freie Schlagworte | TXRF ; reference-free quantitation ; semiconductor surfaces ; contamination ; light elements |
| Zusammenfassung | Total-reflection X-ray fluorescence (TXRF) analysis is a well-established method to monitor lowest level contamination on semiconductor surfaces. Even light elements on a wafer surface can be excited effectively when using high-flux synchrotron radiation in the soft X-ray range. To meet current industrial requirements in non-destructive semiconductor analysis, the Physikalisch-Technische Bundesanstalt (PTB) operates dedicated instrumentation for analyzing light element contamination on wafer pieces as well as on 200 mm and 300 mm silicon wafer surfaces. This instrumentation is also suited for grazing incidence X-ray fluorescence analysis (GIXRF) and conventional energy-dispersive X-ray fluorescence (EDXRF) analysis of buried and surface nanolayered structures, respectively. The most prominent features are a high vacuum load-lock combined with an equipment front end module (EFEM) and a UHV irradiation chamber with an electrostatic chuck (ESC) mounted on an 8-axis manipulator. Here, the entire surface of a 200 mm or a 300 mm wafer can be scanned by monochromatized radiation provided by the plane grating monochromator beamline (PGM) for undulator radiation in the PTB laboratory at the electron storage ring BESSY II. This beamline provides high spectral purity and high photon flux in the range of 78 eV to 1.86 keV. In addition, absolutely calibrated photodiodes and Si(Li) detectors are used to monitor the exciting radiant power respectively the fluorescence radiation. Furthermore, the footprint of the excitation radiation at the wafer surface is well known due to beam profile recordings by a CCD during special operation conditions at BESSY II that allow for drastically reduced electron beam currents. Thus all the requirements of completely reference-free quantitation of TXRF analysis are fulfilled and are to be presented in the present work. The perspectives to arrange for reference-free quantitation using X-ray tube based, table-top TXRF analysis are also addressed. |
