| 摘要 |
A magnetic sensor suitable for sensing an external magnetic field includes a magnetic tunnel junction (MTJ) device. The MTJ device is used to sense an out-of-plane (Z-axis) component of the external magnetic field at a perpendicular direction to the MTJ device. The MTJ device includes a first pinned magnetic layer, a tunnel layer and a magnetic sensing layer. The first pinned magnetic layer has a pinned magnetization perpendicular to the first pinned magnetic layer. The tunnel layer is disposed on the first pinned magnetic layer. The magnetic sensing layer is disposed on the tunnel layer. The magnetic sensing layer has a critical thickness to be at a superparamagnetic range, in which an out-of-plane (Z-axis) magnetic sensitivity is larger than an in-plane (X-axis, Y-axis) magnetic sensitivity. The first pinned magnetic layer, the tunnel layer and the magnetic sensing layer are stacked in a forward sequence or a reverse sequence.
|
