Submicron spin valve magnetoresistive random access memory cell

Abstract

Spin valve magnetoresistive random access memory cells with widths varying from 1.5 to 0.25 μm and an aspect ratio of length/width more than 10 were fabricated and tested. In general, the switching field of the free magnetic layer was found to be inversely proportional to the width of the cell. Adequate pinning was shown for cell width down to 0.75 μm. For 0.5 and 0.25 μm wide cells, the switching field of the free magnetic layer is comparable to the pinning field of the other magnetic layer. So the pinned magnetic layer rotates with the free magnetic layer. The giant magnetoresistive ratio of the cell drops dramatically. Potentially, this may be a fundamental problem for this memory mode. Solutions are proposed.

Controlling of spin orientation in a pseudo-spin valve MRAM cell with pulsed conductor currents

“…PSV materials consist of two magnetic layers with different coercivity, separated with nonmagnetic spacing layer. Selective switching of spin reorientation in the two magnetic layers enables non-destructive read out (NDRO) operation in MRAM [1][2][3] or various spin logic operations [4,5]. Though the tunneling magnetoresistive cell is generally used in current MRAM devices, the PSV cell has potential ability of realizing high density by adopting a sense line design with several memory cells connected in series [6].…”

Influence of sample width on the magnetoresistance and planar Hall effect of Co/Cu multilayers

“…Also, we find that wider samples follow a quite linear trend between coercive field and 1/w, similar to what is seen in other works associated to the influence of Hemagnetizing field. 17,18 However, as the in-plane demagnetizing factor should be below 10 À3 , this does not seem to be a significant factor here.…”

Magnetization switching of a magnetic wire with trilayer structure using giant magnetoresistance effect

“…Sweep rate of the external field is 6 Oe/s. the average hard axis demagnetizing field H d , [11][12][13][14] which can be estimated as…”