A proposal vortex transitional nondestructive read-out Josephson memory cell is successfully fabricated and tested. The memory cell consists of two superconducting loops in which a single flux quantum is stored and a two-junction interferometer gate as a sense gate. The memory cell employs vortex transitions in the superconducting loops for writing and reading data. The vortex transitional memory operation of the cell contributes to improving its sense discrimination and operating margin. The memory cell is activated by two control signals without timing control signals. Memory cell chips have been fabricated using a niobium planarization process. A±21% address signal current margin and a ±33% sense gate current margin have been obtained experimentally. Successful memory operations of a cell driven by two-junction interferometer gates has been demonstrated. The single flux quantum operations of this memory cell makes it an attractive basic element for a high-speed cache memory.

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Extendibility of xray lithography to 130 nm ground rules in complex integrated circuit patterns 0.1 μm AlGaAs/InGaAs high electron mobility transistor fabrication by the new method of thinned resist pattern reversed by metal

High-T c superconducting lines as narrow as 0.8 µm, have been fabricated from Y-Ba-Cu-O films. The films were epitaxially grown on MgO (100) substrates heated at 740°C, by rf magnetron sputtering. The lines were patterned using focused ion-beam lithography and ion-beam etching. The resulting superconducting lines, 1.3 µm wide and 2 mm long, showed a zero resistance temperature of 81 K and a critical current density of 1.5×104 A/cm2 at 77.3 K with smooth surfaces.

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