A new cryogenic memory system

The recently developed "current stretch" technique, a low temperature integration and amplification of sense signals, offers new freedom in the design of cryogenic memory cells. This scheme makes the sense voltage independent of cell switching speed and gives a good signal-to-noise ratio. A memory system using a double hole tin film storage cell driven by cryotron trees is described. Current stretch sensing is done through the trees so that no sense line is required. The cell operating range, which can be made arbitrarily large, has been set at 40 percent in the present study. Cells have been tested at densities of 10³bit/in²and switching speeds of 100 ns. Densities of 10⁴bit/in²appear feasible with existing fabrication techniques. In sizes of 10⁸cells or above, this memory system appears cheaper than any known room temperature technique of equal speed.