Experimental ion-implanted bubble memory device with 16-μm2 cell

This paper describes a 4-μm-period (16 μm²/bit) magnetic bubble device based on ion-implanted propagation patterns. Single-layer LaSmLuBiGa-IG films were implanted with Ne⁺ and He⁺ ions using densified photoresist masking patterns. Coarse (three eighths of a period) minimum features were used in the Permalloy and Al-Cu levels. A 21-Oe overlap bias range was obtained for generation, propagation, transfer, and detection at 55-Oe drive. Generation and detection were demonstrated to have a 39-Oe bias range at 44-Oe drive, and a 39-Oe bias range for minor-loop propagation was obtained at ≥33-Oe drive.