Y. Aoki et al., VICKERS HARDNESS MEASUREMENT OF ION-IMPLANTED MGO, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 91(1-4), 1994, pp. 247-251
The Vickers hardness was measured for single crystals of MgO(100) impl
anted with 130 keV or 1.8 MeV Ar+ ions and with 400 keV Xe2+ ions by m
eans of the indentation technique with an applied load of 0.4-30 mN. I
mplantation with 130 keV Ar+ and 400 keV Xe2+ gave similar results in
hardening of MgO surface layers. In addition, the dose dependence of t
he measured hardness curve showed that a softening mechanism takes pla
ce at high doses. High energy implantation (1.8 MeV Ar+) made a harden
ed surface layer on MgO. This hardened layer also became softer at hig
h doses.