2016
ACL
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T.Pingault, P.S.Pokam-Kuisseu, E.Ntsoenzok, J.P.Blondeau, A.Ulyashin, H.Labrim, B.Belhorma, 'A novel kerf-free wafering process combining stress-induced spalling and low energy hydrogen implantation', Physica Status Solidi C 13 802-806 (2016) doi:10.1002/pssc.201600056
In this work, we studied the potential use of low-energy
hydrogen implantation as a guide for the stress-induced
cleavage. Low-energy, high fluence hydrogen implantation
in silicon leads, in the right stiffening conditions, to
the detachment of a thin layer - around a few hundreds
nm thick - of monocrystalline silicon. We implanted
monocrystalline silicon wafers with low-energy hydrogen,
and then glued them on a cheap metal layer. Upon cooling
down, the stress induced by the stressor layers (hardened
glue and metal) leads to the detachment of a thin silicon
layer, which thickness is determined by the implantation
energy. We were then able to clearly demonstrate
that, as expected, hydrogen oversaturation layer is very
efficient to guide the stress. Using such process, thin silicon
layers of around 710nm-thick were successfully detached
from low-energy implanted silicon wafers. Such
layers can be used for the growth of very good quality
monocrystalline silicon of around 50μm-thick or less.
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