Sensor device having a magnetostrictive force sensor

A sensor device for detecting a force that acts in a prescribed direction of force, comprising:

• a tunnel-magnetoresistive sensor element, as a force sensor element, which is provided with a thin layer system comprising:
• a detection layer of magnetic material having a magnetostriction coefficient λ, where λ≧|5·10−6|;
• a comparatively magnetically harder reference layer or a corresponding reference layer system;
• an intermediate layer of insulating material, as a tunnel barrier, disposed between said detection layer and said reference layer or layer system;
• and electrical connections on said reference layer or reference layer system and on said detection layer, wherein in said detection layer a starting magnetization is established that relative to a magnetization of said reference layer or reference layer system, which is directed at least approximately in the direction of force, forms an angle of other than 0°, so that said starting magnetization of said detection layer is rotated out of a starting position under the effect of the force, wherein the starting magnetization of the detection layer is established by magnetic pre-stressing of the detection layer.