COMPLEMENTARY METAL-OXIDE-SEMICONDUCTOR-COMPATIBLE MICROMACHINED 2-DIMENSIONAL VERTICAL HALL MAGNETIC-FIELD SENSOR - A MODIFIED DESIGN

This article presents the design and characterization of a complementa ry metal-oxide-semiconductor-compatible magnetic-field sensor. The pre sent design is a variation of the original concept for a vertical Hall magnetic-held sensor. Our sensor measures two magnetic-field componen ts parallel to the device surface. The carriers flow in a plane perpen dicular to the device surface. The induced Hall potential is due to th e Lorentz force and measures the intensity of the magnetic field. In o rder to reduce the cross-sensitivity and increase the sensitivity of t he sensor, the carrier regions in the sensor are confined by reverse-b iased p(+) walls. To avoid any premature pinch-off, the p(+) regions a re fabricated skewed at an angle to each other, in such a way that, as the potential difference varies across the carrier regions, the bound aries between the depletion regions remain parallel along the carrier' s path from the central to the outer current contacts. In this way, th e potential impact of carrier confinement is increased, thereby increa sing sensor response by >3X. In addition, the overall sensitivity is i ncreased by 2X while the cross sensitivity is further reduced, in comp arison with the previous sensor. (C) 1998 American Vacuum Society. [S0 734-2101(98)03602-1].