XMR angle sensors

摘要

Embodiments relate to xMR sensors, in particular AMR and/or TMR angle sensors with an angle range of 360 degrees. In embodiments, AMR angle sensors with a range of 360 degrees combine conventional, highly accurate AMR angle structures with structures in which an AMR layer is continuously magnetically biased by an exchange bias coupling effect. The equivalent bias field is lower than the external rotating magnetic field and is applied continuously to separate sensor structures. Thus, in contrast with conventional solutions, no temporary, auxiliary magnetic field need be generated, and embodiments are suitable for magnetic fields up to about 100 mT or more. Additional embodiments relate to combined TMR and AMR structures. In such embodiments, a TMR stack with a free layer functioning as an AMR structure is used. With a single such stack, contacted in different modes, a high-precision angle sensor with 360 degrees of uniqueness can be realized.

主权项

1. An angle sensor for measuring an external magnetic field with 360 degrees of uniqueness comprising:
a tunneling magnetoresistive (TMR) stack having a tunneling barrier layer, a layer exhibiting an anisotropic magnetoresistive (AMR) effect and a first electrode on a first side of the tunneling barrier layer, a second electrode on a second side of the tunneling barrier layer, and first and second contact sets on the first side of the tunneling barrier, wherein the first electrode exhibits an AMR effect; wherein the TMR stack has a first sensor configuration to sense a first condition in the TMR stack when the first contact set is used and a second sensor configuration to sense a second condition in the TMR stack when the second contact set is used, contacts of the first contact set being spaced apart from one another by a first distance and contacts of the second contact set being spaced apart from one another by a second distance different from the first distance.