The values of band offsets in heterojunctions of In0.15Ga0.85AsySb1-y/
Al0.5Ga0.5AszSb1-z and In0.85Ga0.15AsySb(1-y)/Al0.5Ga0.5AszSb1-z with
both quaternaries lattice-matched to GaSb, have been measured by capac
itance-voltage studies. The conduction band offsets are, respectively,
0.75-0.77 and 1.25 eV, with the valence band offsets of -(0.0-0.02) a
nd -0.15 eV. It is shown that the transitivity rule is observed and th
at there is correlation of the valence band offsets with the differenc
e in the Schottky barrier heights of corresponding materials.