The gate oxide tunneling current contributes to the degradation of nano-scaled devices with high-k dielectrics, this current needs to be characterized so the reliability can be predicted. Currently available electrical characterization techniques are not capable of detecting subtle effects, like the vector composition of the gate oxide tunneling current. Therefore, this thesis deals with the use of a combined electrical characterization technique by the application of an external magnetic field. The vector components of the gate oxide current in nano-scale MOSFETs are detected and studied utilizing an electromagnetic characterization technique. The Lorentz’s force is the main basis for this proposed characterization technique; it is used as a tool to deflect the flow of charges in the active region of the MOSFET, and in that way the charges move locally on regions with different conduction properties, this deflection is measured as a tunneling magneto-conductance. The electromagnetic characterization on three leakage current conditions, subthreshold, reverse-biased drain-bulk junction and gate leakage current of an n-type FET device has been achieved. Finally, through the measurement of the magnetoconductance properties of the three leakage current conditions of a MOSFET, an asymmetric and positive magneto-conductance behavior and a nonhomogeneous channel conductance was isolated and has been attributed to the asymmetric strain on the channel MOSFET.