A new class of Hall microsensors with minimal design complexity was suggested and experimentally tested. The devices consisting in n-Si substrate and three n+-strip contacts only are sensitive to a magnetic field parallel to the chip surface. Using a reference voltage generating with a specific bridge circuitry, the linear Hall voltage is extracted and the quadratic geometrical magnetoresistance is fully compensated. The internal noise of the design with a Hall contact located outside the sensor active region is at least ten times smaller than those of the three-contact element with an inside placed output electrode. This leads to enhanced resolution reaching Bmin ap 35 muT. A three-terminal multisensors generating simultaneously and independently strongly asymmetric voltage to the magnetic field direction and a Hall signal were devised too. The devices performance proved undoubtedly that new three-contact sensors could compete with the other well-known vertical Hall elements.
Published in:
Sensors Journal, IEEE
(Volume:9
,
Issue:
7
)
Date of Publication: July 2009