PADReS description copy
Page 4 of 6
I0M
|
The expected performance in terms of micro spot size has been calculated after considering the total demagnification factor of the beamline (equal to 92 along the horizontal direction and 45 along the vertical). For the ideal case of a monochromatic source (for the ID two sections, 562 μm x 73 μm FWHM in the horizontal and vertical directions respectively), a micro spot size of 6.1 μm x 1.6 μm is obtained. By imaging the secondary electrons with the SPELEEM, we measured a FWHM spot size of 25 μm x 2 μm at hv = 140 eV. Keeping into account the angle of incidence (16°) of the photon beam onto the sample, the spot size in the plane normal to the beam is 7 μm x 2 μm, in good agreement with the expected value. At 10 μm the illumination of the field of view becomes already inhomogeneous, affected by striations which reflect the slope errors of the mirrors.
|
 |
Last Updated on Tuesday, 25 October 2011 14:39
