Analysis of 60 nm diam spin dependent tunneling memory cells with thermally assisted writing

摘要

An analysis has been performed for spin dependent tunneling memory cells with a 5 nm thick pinned, storage magnetic layer with a 60 nm diam and with a saturation magnetization of 1000 emu/cm3. In reading, the required pinning fields plus anisotropy fields for the cases of with and without error correction were found to be 79 and 108 Oe. The required total fields for writing for the cases with and without error correction were calculated to be 93 and 129 Oe. The write current needed to provide the total, effective, 129 Oe write field was calculated to be 1.1 mA for the assumed word line structure. The needed heating current through the tunnel cell was calculated to be 41 mu A assuming a tunnel junction and an added resistive layer. A multiple sample read mode with an autozero step and a word read field requires word read currents of 2.50 and 2.75 mA. The multisample, autozero mode has wider margins. If the semiconductor selection matrix can be placed underneath the cells, the calculated cell is 0.022 mu m~2.