Title :
A miniaturized vortex transitional memory cell for a Josephson high-speed RAM
Author :
Nagasawa, S. ; Tahara, S. ; Numata, H. ; Tsuchida, S.
Author_Institution :
Fundamental Res. Labs., NEC Corp., Tsukuba, Japan
Abstract :
We have developed the smallest Josephson nondestructive read-out (NDRO) memory cell, called a vortex transitional(VT) memory cell, for Josephson high-speed RAM. Its size is 22 mu m*22 mu m, which is only 16% of the size of the previously reported VT memory cells used in Josephson 4-kbit RAM. This was achieved by developing a vertically integrated device structure and refining small-junction technology. The cell consists of Nb/AlOx/Nb junctions, three Nb wirings, SiO/sub 2/ insulators and Mo resistors. The VT memory cells functioned properly, with a large operating margin of +or-20%.<>
Keywords :
Josephson effect; aluminium compounds; flux flow; niobium; random-access storage; superconducting junction devices; superconducting memory circuits; type II superconductors; 22 micron; Josephson high-speed RAM; Nb-AlO-Nb; Nb/AlOx/Nb junctions; miniaturized vortex transitional memory cell; nondestructive read-out cell; operating margin; small-junction technology; vertically integrated device structure; Aluminum compounds; Josephson effect; Josephson memories; Niobium; Random access memories;
Conference_Titel :
Electron Devices Meeting, 1992. IEDM '92. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-0817-4
DOI :
10.1109/IEDM.1992.307477
