US 11,706,994 B2
Electric field controlled magnetoresistive random-access memory
Byoung-Chul Min, Seoul (KR); Jun Woo Choi, Seoul (KR); and Hee Gyum Park, Gyeonggi-do (KR)
Assigned to KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
Filed by KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed on May 13, 2020, as Appl. No. 15/930,892.
Claims priority of application No. 10-2019-0063575 (KR), filed on May 30, 2019.
Prior Publication US 2020/0381614 A1, Dec. 3, 2020
Int. Cl. H10N 50/80 (2023.01); H10B 61/00 (2023.01); H10N 50/85 (2023.01)
CPC H10N 50/80 (2023.02) [H10B 61/22 (2023.02); H10N 50/85 (2023.02)] 18 Claims
OG exemplary drawing
 
1. An electric field-controlled magnetoresistive random-access memory (MRAM) comprising at least one one-bit memory cell having a heterogeneous tunnel junction structure composed of a first tunnel junction and a second tunnel junction, wherein:
the first tunnel junction comprises:
a first magnetic layer having a fixed magnetization direction;
a second magnetic layer having a variable magnetization direction that changes according to spin transfer torque when a voltage is applied to the first tunnel junction, thereby providing magnetic information; and
a first insulating layer provided between the first magnetic layer and the second magnetic layer and serving as a tunnel barrier;
the second tunnel junction comprises:
the second magnetic layer; and
a second insulating layer provided on one surface of the second magnetic layer;
the first and second tunnel junctions share the second magnetic layer;
the second tunnel junction has only one magnetic layer being the second magnetic layer;
the one-bit memory cell has only two magnetic layers being the first magnetic layer and the second magnetic layer, and
the second insulating layer is formed of a ferroelectric material configured to undergo spontaneous electric polarization when an electric field is applied thereto to control an electric field applied to the second magnetic layer and induce a change in magnetic anisotropy in the second magnetic layer.