  The determination of the fundamental properties (mass, separation, age,
gravity and atmospheric properties) of brown dwarf companions allows us to
infer crucial informations on their formation and evolution mechanisms.
Spectroscopy of substellar companions is available to date only for a limited
number of objects (and mostly at very low resolution, R<50) because of
technical limitations, i.e., contrast and angular resolution. We present medium
resolution (R=350), coronagraphic long-slit spectroscopic observations with
SPHERE of two substellar companions, HD 1160 B and HD 19467 B. We found that HD
1160 B has a peculiar spectrum that cannot be fitted by spectra in current
spectral libraries. A good fit is possible only considering separately the Y+J
and the H spectral band. The spectral type is between M5 and M7. We also
estimated a T_eff of 2800-2900 K and a log(g) of 3.5-4.0 dex. The low surface
gravity seems to favour young age (10-20 Myr) and low mass (~20 M Jup ) for
this object. HD 19467 B is instead a fully evolved object with a T_eff of ~1000
K and log g of ~5.0 dex. Its spectral type is T6+/-1.
