Techniques for electrically characterizing tunnel junction film stacks with little or no processing

An apparatus for characterizing magnetic tunnel junction film stacks, comprising:

• a multi-point probe having three or more probes, each two of the probes separated by a spacing, the multi-point probe suitable to contact a surface of a magnetic tunnel junction film stack;
• and a resistance module coupled to the multi-point probe and adapted to determine a plurality of resistances from the probes, wherein the smallest spacing between any two of the probes used during at least one resistance measurement is a spacing of 100 microns or less, wherein a resistance measurement by the resistance module at least partially characterizes the tunnel junction film stack, and determining from the plurality of resistances the magnetoreistance of the magnetic tunnel junction.

An apparatus for characterizing magnetic tunnel junction film stacks, comprising:

• a plurality of multi-point probes, each multi-point probe having a plurality of probes, each two of the probes separated by a spacing, where the spacing between the two closest probes for at least several of the multi-point probes is less than 100 microns, each of the multi-point probes suitable to contact a surface of a magnetic tunnel junction film stack;
• and a resistance module adapted to determine a plurality of resistances from the multi-point probes and adapted to be coupled to one or more of the multi-point probes at one time, wherein the resistance module is adapted to measure resistance and measure current, wherein a resistance measurement by the resistance module at least partially characterizes the magnetic tunnel junction film stack and determining from the plurality of resistances the magnetoreistance of the magnetic tunnel junction.