A 380 PS, 9.5 MW JOSEPHSON 4-KBIT RAM OPERATED AT A HIGH BIT YIELD

被引：378
作者：
NAGASAWA, S
HASHIMOTO, Y
NUMATA, H
TAHARA, S
机构：
[1] NEC Corporation, Tsukuba 305
来源：
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY | 1995年 / 5卷 / 02期
关键词：
D O I：
10.1109/77.403086
中图分类号：
TM [电工技术]; TN [电子技术、通信技术];
学科分类号：
0808 ; 0809 ;
摘要：
We have developed a Josephson 4-Kbit RAM with improved component circuits and a device structure having two Nb wiring layers. A resistor coupled driver and sense circuit are improved to have wide operating margins. The fabrication process is simplified using bias sputtering, as a result, its reliability is increased. The RAM is composed of approximately 21000 Nb/AlOx/Nb Josephson junctions, Mo resistors, Nb wirings, and SiO2 insulators. Experimental results show a minimum access time of 380 ps and power dissipation of 9.5 mW. Maximum bit yield of 84% is obtained in minimum magnetic field of about 20 mu G. We confirm that most of fail bits are caused by trapped magnetic flux, and the RAM functions properly for 98% of the memory cells after measuring fail bit map several times.
引用
收藏
页码：2447 / 2452
页数：6
相关论文
共 13 条
[1]  
ABADIR MS, 1983, COMPUT SURV, V15, P175, DOI 10.1145/356914.356916
[2]   MOAT-GUARDED JOSEPHSON SQUIDS [J].
BERMON, S ;
GHEEWALA, T .
IEEE TRANSACTIONS ON MAGNETICS, 1983, 19 (03) :1160-1164
[3]   A FABRICATION PROCESS FOR A 580PS 4KBIT JOSEPHSON NONDESTRUCTIVE READ-OUT RAM [J].
ISHIDA, I ;
TAHARA, S ;
HIDAKA, M ;
NAGASAWA, S ;
TSUCHIDA, S ;
WADA, Y .
IEEE TRANSACTIONS ON MAGNETICS, 1991, 27 (02) :3113-3116
[4]   A FULLY OPERATIONAL 1-KB VARIABLE THRESHOLD JOSEPHSON RAM [J].
KUROSAWA, I ;
NAKAGAWA, H ;
AOYAGI, M ;
KOSAKA, S ;
TAKADA, S .
IEEE JOURNAL OF SOLID-STATE CIRCUITS, 1991, 26 (04) :572-577
[5]   570-PS 13-MW JOSEPHSON 1-KBIT NDRO RAM [J].
NAGASAWA, S ;
WADA, Y ;
HIDAKA, M ;
TSUGE, H ;
ISHIDA, I ;
TAHARA, S .
IEEE JOURNAL OF SOLID-STATE CIRCUITS, 1989, 24 (05) :1363-1371
[6]  
NAGASAWA S, 1994, IEICE T ELECTRON, VE77C, P1176
[7]   380PS, 9.5MW JOSEPHSON 4KBIT RAM [J].
NAGASAWA, S ;
HASHIMOTO, Y ;
NUMATA, H ;
TSUCHIDA, S ;
TAHARA, S .
ELECTRONICS LETTERS, 1994, 30 (10) :761-762
[8]  
NUMATA H, UNPUB IEEE T APPL SU
[9]  
NUMATA H, ISEC 93, P280
[10]   A 4K JOSEPHSON MEMORY [J].
SUZUKI, H ;
FUJIMAKI, N ;
TAMURA, H ;
IMAMURA, T ;
HASUO, S .
IEEE TRANSACTIONS ON MAGNETICS, 1989, 25 (02) :783-788
12