The investigation of the minimum bubble drive field (&Dgr;Hz,min) in ion‐implanted 5‐&mgr;m magnetic garnet films shows that it depends strongly on the implantation conditions such as the implantation energy and dosage. With increasing implantation energy and dosage adjusted so that the maximum damage level remains constant, the &Dgr;Hz,mindecreases monotonically. Varying the dosage while keeping the implantation energy constant leads to a pronounced minimum in &Dgr;Hz,min. Reductions of the &Dgr;Hz,minby as much as 43% from that of the as‐grown films have been achieved by using proper ion implantations. The &Dgr;Hz,minin an ion‐implanted film is found also to be dependent on the applied in‐plane fieldHip. With increasingHip, the minimum drive field increases until finally the as‐grown value is reached. This behavior as well as the dependence of &Dgr;Hz,minon the different ion implantations can be explained qualitatively by a model, assuming a capping layer somewhat buried in the garnet film.