Hall-effect sensors are widely used for proximity sensing, control and condition monitoring purposes. Current technology makes use of the high density 2DEG formed in InGaAs and InAsSb materials to achieve high sensitivity. However, these semiconductors have low bandgap energies (between 0.4 – 1.4 eV) which make them unsuitable for higher temperature operation of more than 150ᵒC. This paper proposes a Hall-effect sensor configuration on AlGaN/GaN Fin-HEMT structure which gives a high sensitivity Hall voltage. It is suitable for system integration and high-temperature applications.