HIGH RESOLUTION PLANAR HALL EFFECT SENSORS

摘要

The present invention discloses a planar Hall-effect sensor with a magnetic sensing region of an elongated shape, wherein, for a ratio of long axis length to short axis length greater than a predetermined number, effective single magnetic domain behavior is exhibited in the sensing region, the sensing having shape-induced uniaxial magnetic anisotropy with the easy axis parallel to the long axis of the magnetic sensing region; further wherein the magnitude of the uniaxial magnetic anisotropy depends on the ratio of the thickness of the sensing region to the length of the short axis.

主权项

1. A planar Hall-effect sensor, comprising:
a. two current-injecting terminals; b. two voltage measuring terminals; and c. a magnetic sensing region of an elongated shape, said shape characterized by:
(a) an easy axis;(b) a long axis;(c) a short axis perpendicular to said long axis;(d) a thickness t;(e) two ends, each of which is electrically connected to one said current-injecting terminal; and,(f) two sides, each of which is electrically connected to one said voltage measuring terminal; wherein, for a ratio of length of said long axis to length of said short axis greater than a predetermined number, effective single magnetic domain behavior is exhibited in said sensing region, with shape-induced uniaxial magnetic anisotropy with said easy axis parallel to said long axis of said magnetic sensing region; further wherein the magnitude of said uniaxial magnetic anisotropy depends on said ratio of said thickness t to said length of said short axis.