  We propose an analytical model to describe the mechanical deformation of
single-crystal diamond following the local sub-superficial graphitization
obtained by laser beams or MeV ion microbeam implantation. In this case, a
local mass-density variation is generated at specific depths within the
irradiated micrometric regions, which in turn leads to swelling effects and the
development of corresponding mechanical stresses. Our model describes the
constrained expansion of the locally damaged material and correctly predicts
the surface deformation, as verified by comparing analytical results with
experimental profilometry data and Finite Element simulations. The model can be
adopted to easily evaluate the stress and strain fields in locally graphitized
diamond in the design of microfabrication processes involving the use of
focused ion/laser beams, for example to predict the potential formation of
cracks, or to evaluate the influence of stress on the properties of opto
mechanical devices.
