PURPOSE: To cover beforhand the effective region of a GdGa garnet (GGG) with a film, coating thereon Pt and then lifting off the same thereby to prevent detrimental influence of dicing.

CONSTITUTION: A photoresist pattern 8 is prepared on a non-magnetic substrate GGG 7, and Pt 9 is evaporated thereon in a length of about 2000 . After lifting the resist off, the substrate is slightly etched with phosphoric acid. Thereafter, a magnetic film 10 is produced by liquid-phase epitaxial growth thereby to obtain a desired magnetic film substrate. An abnormal bubble inhibiting film, an insulating film, a conductor and a permalloy are successively laminated thereon thereby to fabricate a bubble memory chip substrate. Thereafter, the substrate is subjected to dicing along the Pt line 9'. According to this method, there is no magnetic piece in the periphery of the bubble memory chip and hence the bubble memory chip of excellent bubble memory performance characteristics can be obtained.