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arXiv · 1411.4868

Towards wafer scale inductive characterization of spin transfer torque critical current density of magnetic tunnel junction stacks

Sibylle Sievers·Niklas Liebing·Santiago Serrano-Guisan·Ricardo Ferreira·Elvira Paz·Ambra Caprile·Alessandra Manzin·Massimo Pasquale·Witold Skowroński·Tomasz Stobiecki·Karsten Rott·Günter Reiss·Jürgen Langer·Berthold Ocker·Hans Werner Schumacher
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Abstract

We explore the prospects of wafer scale inductive probing of the critical current density $j^{c0}$ for spin transfer torque switching of a CoFeB/MgO/CoFeB magnetic tunnel junction with varying MgO thickness. From inductive measurements magnetostatic parameters and the effective damping are derived and $j^{c0}$ is calculated based on spin transfer torque equations. The inductive values compare well to the values derived from current induced switching measurements on individual nanopillars. Using a wafer scale inductive probe head could in the future enable wafer probe station based metrology of $j^{c0}$.

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Sibylle Sievers, Niklas Liebing, Santiago Serrano-Guisan, Ricardo Ferreira, Elvira Paz, Ambra Caprile, Alessandra Manzin, Massimo Pasquale, Witold Skowroński, Tomasz Stobiecki, Karsten Rott, Günter Reiss, Jürgen Langer, Berthold Ocker, Hans Werner Schumacher. 2014-11-18. Towards wafer scale inductive characterization of spin transfer torque critical current density of magnetic tunnel junction stacks. https://doi.org/10.1109/tmag.2014.2357808

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