These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: X-ray spectrometry and spectrum image mapping at output count rates above 100 kHz with a silicon drift detector on a scanning electron microscope.
    Author: Newbury DE.
    Journal: Scanning; 2005; 27(5):227-39. PubMed ID: 16268175.
    Abstract:
    A third-generation silicon drift detector (SDD) in the form of a silicon multicathode detector (SMCD) was tested as an analytical x-ray spectrometer on a scanning electron microscope. Resolution, output count rate, and spectral quality were examined as a function of the detector peaking time from 8 micros to 250 ns and over a range of input count rate (dead time). The SDD-SMCD (50 mm2 active area) produced a resolution of 134 eV with a peaking time of 8 micros. The peak width and peak channel were nearly independent of the input count rate (at 8 micros peaking time, the peak width degradation was 0.003 eV/percent dead time and peak position change was -0.7 eV over the dead time range tested). Maximum output count rates as high as 280 kHz were obtained with a 500 ns peaking time (188 eV resolution) and 500 kHz with a 250 ns peaking time (217 eV resolution). X-ray spectrum imaging was achieved with a pixel dwell time as short as 10 ms (with 1.3 ms overhead) in which a 2048 channel (10 eV/channel) spectrum with 2-byte intensity range was recorded at each pixel (scanned at 128 x 128). With a 220 kHz output count rate, a minor constituent of iron (present at a concentration of 0.04 mass fraction or 4 weight %) in an aluminum-nickel alloy could be readily detected in the x-ray maps derived from the x-ray spectrum image database accumulated in 185 s.
    [Abstract] [Full Text] [Related] [New Search]