Influence of silicon anisotropy on the sensitivity of Hall devices and on the accuracy of magnetic angular sensors

An orientation dependence has been measured for vertical Hall (VH)-sensors and for horizontal CMOS Hall plates fabricated on n-doped (1 0 0) silicon w afers. A sensitivity difference up to 15% at 6.5 T is measured for VH-senso rs in the (0 1 0) plane in comparison with the one in the (0 1 T) plane. Wh en non-conventional orientations are used in an angular sensor, an angular shift up to 4 degrees is measured at 2 T. Planar Hall effect in CMOS device s can be minimized by a proper choice of the sensor orientation. A model is derived that relates these effects to the silicon material anisotropy. Des ign rules have been derived for the realization of highly linear and accura te silicon Hall magnetometers. (C) 2001 Elsevier Science B.V. All rights re served.