Oscillator element and method for producing the oscillator element

摘要

An oscillator element according to one embodiment of the present invention includes a magnetoresistive element having a magnetization free layer, magnetization fixed layer, and a tunnel barrier layer. Provided on the magnetization free layer are a protection layer and an electrode having a point contact section where the electrode is partially in electrical contact with the protection layers. An interlayer insulating film is provided between the electrode and the protection layer. The area of the interface between the magnetization free layer and the tunnel barrier layer is larger than the surface area of the point contact section. Moreover, a portion of the protection layer in contact with the interlayer insulating film has a smaller thickness in a surface normal direction than the portion of the protection layer in contact with the electrode.

主权项

1. An oscillator element comprising:
a magnetoresistive element having:
a magnetization free layer whose magnetization direction is variable,a magnetization fixed layer whose magnetization direction is fixed in one direction, anda tunnel barrier layer interposed between the magnetization free layer and the magnetization fixed layer; a first protection layer provided on and in contact with the magnetization free layer; a second protection layer provided on and in contact with the first protection layer; an electrode provided on the second protection layer in such a manner that the second protection layer is arranged between the first protection layer and the electrode, and the electrode is electrically contacted with the second protection layer; and an interlayer insulating film provided between the first protection layer and the electrode in such a manner that the electrode has a point contact section where the electrode is partially in electrical contact with the second protection layer, wherein an area of an interface between the second protection layer and the electrode is smaller than an area of an interface between the first protection layer and the magnetization free layer, wherein a portion of the first protection layer in contact with the interlayer insulating film has a smaller thickness in a surface normal direction than a portion of the first protection layer in contact with the second protection layer, wherein a laminate of the first protection layer and the second protection layer is formed to have a raised portion, wherein an upper surface of the raised portion is electrically contacted with the point contact section of the electrode, and wherein a portion of the laminate other than the raised portion has a smaller thickness in a surface normal direction than the raised portion in a surface normal direction.