A magnetic, thin-film, integrated circuit memory system

A memory system comprising uncased integrated circuits, evaporated wires, and magnetic, thin-film storage elements has been fabricated and tested. The 1536-bit memory system is contained on one side of a 3-by 4 1/2-inch glass substrate. All system wiring on the substrate is formed by evaporating aluminum through masks. All system circuits are contained on 182 silicon chips, each 0.050-inch square, and the chips are ultrasonically bonded directly to the evaporated aluminum. Data are presented on the operation of the selection system, of the recirculation loops, and of a portion of the memory system. Operation of the complete memory system was precluded by oscillations which developed in the system as recirculation loops were added. All subsections of the memory system function properly except for the recirculatinn loops. The origin of the oscillations and the techniques for eliminating them are discussed. The data obtained in fabricating and testing partially populated systems indicate that the fabrication techniques are practical.