MRAM architecture for low power consumption and high selectivity
View Patent ↗The present invention provides a magnetoresistive memory cell ( 30 ), comprising a magnetoresistive memory element ( 31 ), a first current line ( 32 ) and a second current line ( 33 ), the first and the second current line ( 32, 33 ) crossing each other at a cross-point region but not being in direct contact. According to the invention, a bridging element( 34 ) connects the first and second current lines ( 32, 33 ) in the vicinity of the cross-point region. The bridging element ( 34 ) is magnetically couplable to the magnetoresistive memory element ( 31 ). An advantage of the MRAM architecture according to the present invention is that it allows lower power consumption than prior art devices and high selectivity during writing. The present invention also provides a method of writing a value in a matrix of magnetoresistive memory cells ( 30 ) according to the present invention, and a method of manufacturing such magnetoresistive memory cells ( 30 ).
1. Magnetoresistive memory cell, comprising a magnetoresistive memory element, a first current line and a second current line, the first and the second current line crossing each other at a cross-point region but not being in direct contact, wherein a bridging element connects the first and second current lines in the vicinity of the cross-point region, the bridging element is magnetically couplable to the magnetoresistive memory element, and the bridging element comprises at least a first component which lies in a plane parallel to the first and second current lines and a second component which is perpendicular thereto.
2. Magnetoresistive memory cell according to claim 1 , wherein the bridging element is a conductive structure.
3. Magnetoresistive memory cell according to claim 1 , there being a separation device between the bridging element and the first current line or between the bridging element and the second current line.
4. Magnetoresistive memory cell according to claim 1 , there being a separation device in between components of the bridging element.
5. Magnetoresistive memory cell according to claim 3 , wherein the separation device has a non-linear current-voltage characteristic.
6. Magnetoresistive memory cell according to claim 5 , wherein the separation device has a symmetric non-linear current-voltage characteristic.
7. Magnetoresistive memory cell according to claim 1 , the bridging element having a center point, wherein the magnetoresistive memory element is located at the center point of the bridging element.
8. Matrix of magnetoresistive memory cells, each magnetoresistive memory cell comprising a magnetoresistive memory element, the magnetoresistive memory cells being linked together to form logically organized rows and columns, each row being provided with a first current line and each column being provided with a second current line, the first and the second current lines crossing each other at cross-point regions, wherein bridging elements connect the first and second current lines in the vicinity of the cross-point regions, and the bridging elements are magnetically couplable to the magnetoresistive memory elements and each bridging element comprises at least a first component which lies in a plane parallel to the first and second current lines and a second component which is perpendicular thereto.
9. Matrix according to claim 8 , wherein every memory cell is provided with a selection transistor.
10. Matrix according to claim 8 , wherein every row of memory cells is provided with a sense line.
11. Method of writing a value in a matrix of magnetoresistive memory cells, each magnetoresistive memory cell comprising a magnetoresistive memory element, the magnetoresistive memory cells being linked together to form logically organized rows and columns, each row being provided with a first current line and each column being provided with a second current line, the first and the second current lines crossing each other at a cross-point regions in the memory cells, each memory cell being provided with a bridging element conductively connecting the first current line and the second current line, the method comprising sending a current through a selected first current line, through a selected bridging element and through a selected second current line, the bridging element conductively connecting the first current line and the second current line through a separation device, the method furthermore comprising sending current through the separation device and wherein the bridging element comprises at least a first component which lies in a plane parallel to the first and second current lines and a second component which is perpendicular thereto.