On the influence of strong magnetic field on MOS transistors

This paper presents a study on the influence of strong magnetic field on NMOS transistors' electrical characteristics. Experiments have been carried out in a small animal 7T MRI scanner, and have shown that up to 7T the influence exists but remains manageable. It is demonstrated that it depends on the transistor size, on the orientation of the chip inside the field, and on the gate-to-source voltage. A theoretical analysis in good agreement with experiments has been developed. Extrapolation to ultra-high field, i.e. above 10T, shows that at such a field the influence may be challenging, and that it can be lowered by using high overdrive voltage V
_gs
-V
_th
.