  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
$j^{c0}$.
