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

Yield (counts per 5 uC)
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3keV As 2E15 ion/cm 2 - Si profiles: MEIS and XRD
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Depth (nm)
This procedure demonstrates the excellent agreement of the SPER thickness
measured by the two techniques. In fact both of the comparisons of MEIS with X-ray
studies (section 6.2.3.3 and 6.3.3.3) give corroborative results. It has again been shown
how MEIS can be used as a starting point in the interpretation of the results of the X-ray
studies, which could become increasingly useful for future defect studies.
6.4 SOI regrowth
6.4.1 Introduction
Annealing studies have been carried out to investigate the regrowth behaviour of
silicon on insulator (SOI). SOI wafers are produced from two bulk Si wafers. An oxide
layer is grown on one of the wafers, which subsequently forms the buried oxide layer.
Hydrogen ions are implanted through the oxide into the underlying silicon and form a
damage layer containing H bubbles at the end of the ions range. The two wafers are then
bonded together using Van der Waals forces. The implanted wafer is then cut across the
damage plane leaving a thin layer of Si, which is then polished, on top of a buried oxide
layer (23). The process is called Smart Cut (24, 25). The wafers used in these studies
have either a 60 nm, 88 nm or 100 nm Si layer on top of a buried SiO2 layer
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virgin
Epi as-implanted
Epi 550C 200s
Epi 600C 20s
Epi 650C 10s
Epi 700C 10s
Figure 6.23 Comparison of MEIS depth profiles with the strain profile from XRD after
rescaling of the depth.
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