Details

Autor(en) / Beteiligte

• Jeong, W. C.
• Park, J. H.
• Koh, G. H.
• Jeong, G. T.
• Jeong, H. S.
• Kim, Kinam

Titel

Switching field distribution in magnetic tunnel junctions with a synthetic antiferromagnetic free layer

Ist Teil von

• Journal of applied physics, 2005-05, Vol.97 (10), p.10C905-10C905-3

Ort / Verlag

American Institute of Physics

Erscheinungsjahr

2005

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• By replacing the traditional single magnetic free layer in magnetic random access memory (MRAM) with a synthetic antiferromagnetic (SAF) layer composed of two antiferromagnetically coupled layers, the possibility of the kink generation has been suppressed to a minimum level and the normalized free-layer shift has been reduced from 15% to less than 5%. These phenomena are thought to be from the reduction of the effective thickness and magnetic moment by introducing a SAF free layer. Since the SAF free layer decreases the magnetostatic interaction with the pinned layer, free-layer shift is also decreased. A SAF free layer forms a closed magnetic loop between two antiferromagnetically coupled layers. Therefore, it increases a tendency to become a single domain and its switching field distribution is enhanced. With the optimized SAF free layer, array quality factor [AQF, σ ( Hc ) ∕ Hc ] is increased to more than 10 and switching window could be obtained which is the area to be selectively switched in the memory cell array. When adopted in a 64 - kb MRAM, it is confirmed that cells can be selectively switched without the disturbance to the other cells.