Abstract: A method for checking value documents includes checking a security element having a plurality of magnetic regions, including a high-coercivity magnetic region, optionally a low-coercivity magnetic region and optionally a combined magnetic region which contains the high-coercivity as well as the low-coercivity magnetic material, and optionally a soft-magnetic magnetic region. After the magnetization of all the magnetic regions in a first direction, first magnetic signals of the security element are detected with a first magnetic detector. Subsequently, a second magnetization is performed wherein the low-coercivity magnetic material is remagnetized anti-parallel to the first magnetization, but the high-coercivity magnetic material remains aligned in the first magnetization direction. Second magnetic signals are detected with a second magnetic detector.

Abstract: A reader sensor comprises a first shielding layer, a second shielding layer, a read element formed therebetween, and a pair of permanent magnet layer respectively placed on two sides of the read element; and it further comprises a magnetic field generating means formed beside the read element and arranged for providing a magnetic field with a direction perpendicular to the first shielding layer and the second shielding layer, thereby stabilizing the reading performance of the reader sensor. The invention can stabilize the reading performance, ameliorate the unstable defective reader sensor, and decrease the waste and the manufacturing cost. The present invention also discloses a magnetic head, a HGA and a disk drive unit.

Abstract: A magnetic head having a sensor with a free layer, the free layer having a magnetic moment. Hard bias layers are positioned towards opposite track edges of the sensor, the bias layers stabilizing the magnetic moment of the free layer. An antiparallel (AP) pinned layer structure is positioned toward each of the hard bias layers, each AP pinned layer structure having at least two pinned layers with magnetic moments that are self-pinned antiparallel to each other. Each AP pinned layer structure stabilizes a magnetic moment of the hard bias layer closest to it. An antiferromagnetic layer is positioned toward each of the AP pinned layer structures, each antiferromagnetic layer stabilizing a magnetic moment of pinned layer closest to it.

Abstract: Multilayer permanent magnet films comprising at least two permanent magnet layers separated by an interlayer are disclosed. In one embodiment, the multilayer permanent magnet film includes an interlayer deposited on a first permanent magnet layer, a seed layer deposited on the interlayer, and a second permanent magnet layer deposited on the seed layer. The permanent magnet layers may comprise a material such as CoPt, while the seed layer may comprise a material such as TiW. The interlayer may comprise a material such as Ta. The multilayer permanent magnet films possess favorable properties such as high magnetic coercivity (Hc) and high remnant magnetization (MR) at thicknesses which yield high magnetic fields. The films may be used in applications such as current perpendicular to the plane (CPP) magnetic sensors in which the multilayer permanent magnet film is used to magnetically bias the sensor.

Abstract: A magnetoresistive-effect device includes a multilayer film, hard bias layers arranged on both sides of the multilayer film, and electrode layers respectively deposited on the hard bias layers. The electrode layers are formed, extending over the multilayer film. Under the influence of the hard bias layers arranged on both sides of the multilayer, the multilayer film, forming the magnetoresistive-effect device, has, on the end portions thereof, insensitive regions which exhibit no substantial magnetoresistive effect. The insensitive region merely increases a direct current resistance. By extending the electrode layers over the insensitive regions of the multilayer film, a sense current is effectively flown from the electrode layer into the multilayer film. With a junction area between the electrode layer and the multilayer film increased, the direct current resistance is reduced, while the reproduction characteristics of the device are thus improved.

Abstract: The present invention is a magnetoresistive (MR) sensor (100) that combines the advantages of abutted junction structure and regular overlaid structure. The abutted junction design is used with the soft adjacent layer (SAL) (108) and the overlaid structure is used with the MR element (120). The method of making the MR sensor (100) comprises depositing SAL (108) on top of the gap layer (106) and depositing spacer material (110) on top of the SAL (108). A mask (130) is placed over the central region of the spacer material (110) and SAL (108). The spacer material (110) and SAL (108) are removed in the areas not covered by the mask (130). An underlayer material (112) is deposited in the areas where the SAL (108) and spacer material (110) were removed. A hard-biasing material (114) is deposited on top of the underlayer (112).