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

Hall effect measurements have been carried out on these samples to find their sheet
resistance and the activated dose.
The second part of this section uses identical implant conditions and a variety of
anneals. This work forms part of a study carried out in a comparison with X-ray
techniques at the ESRF to develop X-ray techniques to study defect evolution. The
specific techniques used were GI-DXS, SR, and XRD. More information on these
techniques and studies can be found in (18-20). MEIS has proved to be particularly
useful, providing a basis for the interpretation of some of the X-ray results. It is found
that the results obtained from MEIS and XRD are in excellent agreement.
6.3.2 Isothermal and Isochronal series
6.3.2.1 Isothermal series
A crystalline Cz Si (100) wafer was implanted with 3 keV As + and a fluence of
2E15 cm -2 . These implant conditions are typical in these studies. The wafer was split
into small samples which were annealed at the University of Salford at a temperature of
600 °C for different durations from 5s to 120s. MEIS was carried out with a 100 keV
He + beam using the [īīı] channelling direction and the analyser was positioned to record
the [332] and [111] blocking directions. Results presented here were taken from the
[111] blocking direction. SIMS analysis was carried out using 0.5 keV and 0.25 keV
Cs + beams. Additionally Hall effect measurements were carried out on these samples by
ITC-IRST staff using the van der Pauw technique and facilities at the University of
Surrey.
The MEIS energy spectra for the [111] blocking direction is shown in Figure
6.10. Included in the figure is the spectrum from the as-implanted sample and the
random level from an amorphous Si sample. Depth scales are indicated on the figure for
scattering off Si and As. Depth profiles of Si and As are shown in the top and bottom of
Figure 6.11 respectively.
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