A new microsystem for very high-accuracy magnetic measurement of all t
hree field components is presented. A single silicon die incorporating
eight sensor devices is mounted on a support and then cut. This galva
nic separation is essential, since the applied technology of vertical
Hall devices yields very high-quality devices, but does not provide fo
r the isolation. In this way perfect alignment of the sensing directio
ns of the sensors is achieved. All sensors are arranged in such a way
that their signals can be combined to represent the x, y and z compone
nts of the magnetic flux density in the centre point of the system. Th
e active volume is about 2 mm x 2 mm x 0.2 mm and the precision of the
alignment is higher than 0.1 degrees. Measurements of cross-current a
nd cross-sensitivity between the two in-plane axes of an identical but
uncut sensor prove the necessity of cutting for achieving an accuracy
of better than 1 parts per thousand. (C) 1998 Elsevier Science S.A. A
ll rights reserved.