Patent ID: 7059201

Claim:
A method of sensing pressure in which applied pressure causes a change in the magnetization vectors of ferromagnetic layers within the device and a corresponding change in resistance that can be sensed upon application of an externally supplied voltage comprising the steps of: providing a sensing device with a sensor including plurality of layers, the plurality of layers comprising a non magnetic insulating barrier layer disposed between at least two ferromagnetic layers which are in an initial state such that their magnetization vectors are stable with respect to each other, and at least one of the ferromagnetic layers having non-zero magnetostriction; and sensing the resistance in the plurality of layers upon application of pressure while the externally supplied voltage is applied, the applied pressure causing the magnetization vector of at least one of the ferromagnetic layers to rotate from the initial state through the property of magnetostriction and thereby changing the resistance to a tunneling current produced by the applied voltage that flows in a direction orthogonal to a plane of the plurality of layers.