A novel structure for three-dimensional silicon magnetic transducers to improve the sensitivity symmetry

A three-dimensional silicon magnetic transducer with symmetric sensitivities in the x-, y- and z-directions and small cross sensitivity has been demonstrated. Devices are based on a design of a vertical Hall structure using the surrounding trench and symmetric design to suppress the cross sensitivity. The fabrication process is simple and can be used as a part of a standard integrated circuit process. The results show that almost equal sensitivities in all three components of magnetic field can be obtained by coating Ni/Co thin films on the backside of the substrates. The cross sensitivity is only 1.3% of the sensitivity.