  We examine the possibility of intrinsic interface states bound to the plane
of In-Sb chemical bonds at InAs/AlSb interfaces. Careful parameterization of
the bulk materials in the frame of the extended basis spds^* tight-binding
model and recent progress in predictions of band offsets severely limit the
span of tight-binding parameters describing this system. We find that a
heavy-hole like interface state bound to the plane of In-Sb bonds exists for a
large range of values of the InSb/InAs band offset.
