Ion migration effects in r.f. “sputter cleaning” of dielectric films

Abstract We have shown that r.f. backsputtering or “sputter cleaning” of dielectric films may cause: (1) the transfer of impurities from one sample to another or from the substrate table to previously clean samples; and (2) ion migration effects within SiO 2 films which are expected to cause gross degradation of “sputter-cleaned” devices. Such degradation may not be annealable, since annealing does not cause the removal of mobile impurities, as has been shown previously. These results are in agreement with the previously presented theory of the ion migration process.