  The ability to generate a change of the lattice parameter in a near-surface
layer of a controllable thickness by ion implantation of strontium titanate is
reported here using low energy He+ ions. The induced strain follows a
distribution within a typical near-surface layer of 200 nm as obtained from
structural analysis. Due to clamping effect from the underlying layer, only
perpendicular expansion is observed. Maximum distortions up to 5-7% are
obtained with no evidence of amorphisation at fluences of 1E16 He+ ions/cm2 and
ion energies in the range 10-30 keV.
