RIE planarization process for magnetic bubble devices.

A reactive ion etching process, which planarizes the silicon dioxide film deposited over steps in AlCu conductor patterns, has been developed for wide gap magnetic bubble devices. A conventional fabrication sequence was used through deposition of the spacer SiO2 layer which isolates AlCu conductors from permalloy propagate elements. Prior to permalloy deposition, however, a thick photoresist layer was spin-coated on the SiO2 layer and hard-baked to form a planar surface.