  We demonstrate that the long-lived bound states (super-molecules) can exist
in the dilute limit when we tune the shape of effective potential between polar
molecules by an external microwave field. Binding energies, average sizes, and
phase diagrams for both s-orbital (bosons) and p-orbital (fermions) dimers are
studied, together with bosonic trimer states. We explicitly show that the non-
adiabatic transition rate can be easily tuned small for such ground state
super-molecules, so that the system can be stable from collapse even near the
associated potential resonance. Our results, therefore, suggest a feasible cold
molecule system to investigate both novel few-body and many-body physics (for
example, the p-wave BCS-BEC crossover for fermions and the paired condensate
for bosons) that can not be easily accessed in single species atomic gases.
