  This work reports on the effect of high temperature annealing on the
electrical properties of p-type implanted 4H-SiC. Ion implantations of
Aluminium (Al) at different energies (30 - 200 keV) were carried out to achieve
300 nm thick acceptor box profiles with a concentration of about 1020 at/cm3.
The implanted samples were annealed at high temperatures (1675-1825 {\deg}C).
Morphological analyses of the annealed samples revealed only a slight increase
of the surface roughness RMS up to 1775{\deg}C, while this increase becomes
more significant at 1825{\deg}C (RMS=1.2nm). Room temperature Hall measurements
resulted in a hole concentration in the range 0.65-1.34x1018/cm3 and mobility
values in the order of 21-27 cm2V-1s-1. The temperature dependent electrical
measurements allowed to estimate an activation energy of the Al-implanted
specie of about 110 meV (for the post-implantation annealing at 1675{\deg}C)
and a fraction of active p-type Al-dopant ranging between 39% and 56%. The
results give useful indications for the fabrication of 4H-SiC JBS and MOSFETs.
