Design and characteristics of 4 µm period ion-implanted bubble devices with major line block replicate gate

A block replicate gate composed of an ion-implanted minor loop and a permalloy major line has been developed for 4 μm period bubble devices. This gate employs a hybrid permalloy and ion-implanted bubble device with no junction between the patterns. Test chips incorporating this replicate gate, the folded minor loop, and the cusp-to-cusp bidirectional transfer gate have been fabricated and characterized for a 100 kHz triangular drive field. A bias field margin of 30 Oe was obtained at 70 Oe ± 10 % peak drive field.