This thesis introduces a model for characterizing 2D rectangular and sector split-drain MAGFETs using COMSOL Multiphysics software. A split-drain MAGFET is a magnetic field-sensitive MOSFET with two or more drains, capable of detecting magnetic fields and converting them into voltage or current signals. The thesis examines various MAGFET parameters to analyze the impact of channel shape, length, width, and drain gaps on sensor sensitivity. The findings indicate that sector MAGFETs with the smallest possible drain gap, a sector angle between 60-80 degrees and a minimum channel length of 50 μm offer the highest sensitivity.

Furthermore, a high-gain, fully differential folded cascode chopper amplifier was designed to enhance the small MAGFET signal and mitigate flicker noise, a significant issue for CMOS-based magnetic sensors. The amplifier, designed using UMC 180 nm CMOS process technology, achieves a DC gain of 78 dB and a bandwidth of 10.8 kHz. It effectively amplifies and eliminates noise from a 1 nA differential current signal of the MAGFET output, corresponding to approximately 1 mT detected magnetic field.