Damage formation and annealing studies of low energy ion implants ...

Figure 4.13 Variation in the kinematic factor K with scattering angle, for different
atom / He or H combinations.
Figure 4.14 Illustration of the double alignment scattering configuration used in the
MEIS experiments, showing the shadowing and blocking.
Figure 4.15 Figure 4.15 MEIS 2D data output (left) of an As implanted Si sample.
Indicated is the position of the angular cut and the two cuts along the
energy axis of the [332] and [111] blocking dips. The corresponding
angular spectrum is plotted in the top right of the figure and the
corresponding energy spectra are given in the bottom right of the figure.
Figure 4.16 Typical MEIS spectra for different samples with a 100 keV He beam and
using the [īīı] channelling and [ııı] blocking directions. The effect of
energy straggling and system resolution on the gradient of the low
energy edge of the peaks and differences in dechannelling level for
different amorphous layer widths are highlighted.
Figure 4.17 Comparison of depth scales calibrated using inelastic energy loss rates
from SRIM 2000 (top) and SRIM 2003 (bottom). Gaussian distributions
have been fitted to the peaks and dashed lines have been placed through
the centre for clarity.
Figure 4.18 He inelastic energy loss rates in Si as a function of energy, taken from
SRIM 2000 and SRIM 2003. The function, of a best fit to the values
from SRIM 2003 is given.
Figure 4.19 a) Screen shot of the depth scale program showing the variable input
parameters. b) An example of the result of a calculation. The relationship
between scattering depth and energy (x) for the two scattering angles is
given at the bottom.
Figure 4.20 Example of conversion from an energy scale (top) to a depth scale
(bottom). Depth scales are specific to individual elements. For this
example only the As peak (in red) is correctly converted. The rest of the
spectrum (dashed line) is effectively meaningless.
Figure 4.21 Example of the difference between depth spectra calibrated using the
surface approximation method and the computer program for a 3 keV As
as-implanted sample.
Figure 4.22 Set up for van der Pauw measurements.
Figure 4.23 Salford ultra low energy ion beam system.
Figure 5.1 MEIS energy spectra showing the growth of the Si damage and As
dopant yield as a function of fluence for 2.5 keV As + ion implantation
into virgin Si at room temperature.
Figure 5.2 Depth profiles of displaced Si and As implant atoms obtained from the
MEIS energy spectra in Figure 5.1. TRIM calculated Si vacancy and
ix