AVS 60th International Symposium and Exhibition
    Synchrotron Analysis Focus Topic Wednesday Sessions
       Session SA+AS+MI+SS-WeM

Paper SA+AS+MI+SS-WeM12
Portable versus Synchrotron TXRF Analysis

Wednesday, October 30, 2013, 11:40 am, Room 203 C

Session: Synchrotron and Imagery: PEEM, Nano-ARPES and Others (8:00-9:40 am)/Synchrotron TXRF and Related Techniques (10:40 am-12:00 pm)
Presenter: J. Kawai, Kyoto University, Japan
Authors: J. Kawai, Kyoto University, Japan
Y. Liu, Kyoto University, Japan
S. Imashuku, Kyoto University, Japan
Correspondent: Click to Email
Total reflection X-ray fluorescence (TXRF) analysis is a micro (absolute amount is less than pg) and trace (relative concentration is less than ppb) analysis method. When synchrotron X-rays are used, the minimum detection limit becomes down to fg for transition metals. However the synchrotron radiation is an elemental selective method, and thus overall elements are not detectable. On the other hand, synchrotron radiation can eliminate the interference of elements whose analytical lines overlap, such as Ba and Ti, As and Pb. The TXRF spectrometers can be classified into three categories: (i) synchrotron radiation TXRF, (ii) high power X-ray tube (kW) TXRF, and (iii) low power (1-50 W) desk top TXRF. Type (i) achieves highest sensitivity, with WD-TXRF spectrometer (wavelength dispersive), down to fg, however ED (energy dispersive type) is also used, where polarization is additionally used to reduce the scattering of incident X-rays. Type (ii) is used for routine analysis of Si wafer analysis (ISO standard methods), but due to the recent progress of the semiconductor processing, the detection limit is not enough for the advanced semiconductor processing systems. Type (iii) is again classified into monochromatic and non-monochromatic types. Monochromatic type needs 50 W X-ray tube (cooling by fan), but non-mono type is possible only by 1 W X-ray tube. The sensitivity is comparable. Type (iii) is mainly used for environmental analysis, toxic elements analysis, and water quality analysis. We must also consider the sensitivity of elements for mass spectrometry such as SIMS and ICP-MS. These methods are sometimes more sensitive than synchrotron radiation TXRF. Most versatility method is the non-monochromatic X-ray tube (1 W) type portable TXRF spectrometer, by which we can analyze something toxic materials, whether it is truely toxic or not toxic. Several examples which show the ability of the low power TXRF, such as laboratory hazard analysis, will be presented.