Films of Bi2Sr2CaCu2Oyhave been prepared by diffusing Bi2CaCu2O5into Sr2CaCu2O5. Examination by x‐ray diffraction and scanning electron microscopy showed a highly preferred orientation of columnar grains with the [100] axis normal to the surface. The maximum oriented texture was for a film thickness of 76 &mgr;m for thicknesses between 51 and 150 &mgr;m. The preferred orientation existed up to the surface of the sample, and there was no evidence of an unreacted region at the surface when the diffusion was done for at least 3 days. The films had the usual superconducting transition of the 2212 phase.