摘要:
A magnetoresistive (MR) read transducer comprising a thin film MR layer formed of ferromagnetic material and a nonmagnetic thin film spacer layer in contact with the MR layer. The spacer layer comprises a material selected from the group consisting of nichrome and nichrome with chromium oxide. A thin film of soft magnetic material is deposited in contact with the spacer layer so that a transverse bias is produced in at least a part of the MR layer. A feature of the invention is that the resistivity of the spacer layer can be chosen by selected the ration of nichrome to chromium oxide in the spacer layer. In a specific embodiment the spacer layer extends over only the central region of the MR layer. In case the MR layer is a nickel based alloy, a wet chemical etching process using an etchant comprising an aqueous solution of ceric ammonium nitrate and acetic acid can be used pattern the spacer layer.
摘要:
A magnetoresistive (MR) read transducer comprising a thin film MR layer formed of ferromagnetic material and a nonmagnetic thin film spacer layer in contact with the MR layer. The spacer layer comprises a material selected from the group consisting of nichrome and nichrome with chromium oxide. A thin film of soft magnetic material is deposited in contact with the spacer layer so that a transverse bias is produced in at least a part of the MR layer. A feature of the invention is that the resistivity of the spacer layer can be chosen by selecting the ratio of nichrome to chromium oxide in the spacer layer. In a specific embodiment the spacer layer extends over only the central region of the MR layer. In case the MR layer is a nickel based alloy, a wet chemical etching process using an etchant comprising an aqueous solution of ceric ammonium nitrate and acetic acid can be used to pattern the spacer layer.
摘要:
A magnetoresistive (MR) sensor comprising a sputtered layer of ferromagnetic material and a sputtered layer of antiferromagnetic nickel-manganese (Ni-Mn) to provide an exchange coupled longitudinal bias field in the MR element is described. The antiferromagnetic layer overlays the MR layer and may be patterned to provide the longitudinal bias field only in the end regions of the MR layer. Alternatively, the antiferromagnetic layer can underlay the MR layer with a Zr underlayer to enhance the exchange-coupled field. As initially deposited, the Ni-Mn layer is face-centered-cubic and exhibits little or no exchange-coupled field. After one annealing cycle at a relatively low temperature, the Ni-Mn layer is face-centered-tetragonal and exhibits increased crystallographic ordering and provides sufficient exchange coupling for the MR element to operate. Addition of chromium to the Ni-Mn alloy provides increased corrosion resistance.
摘要:
An improved CoPt alloy magnetic recording disk for horizontal recording has a magnetic recording layer which includes oxygen, the oxygen being present preferably in the range of approximately 5 to 30 atomic percent. The resulting disk structure has substantially decreased intrinsic media noise at high linear recording density.
摘要:
A cobalt alloy disk for horizontal magnetic recording has both high coercivity and low noise at high recording density. The magnetic layer in the disk contains, in addition to the cobalt alloy material, an oxide of one or more "impurity" elements which have both a relatively low solubility in cobalt and a high affinity for oxygen. Such elements include yttrium (Y), silicon (Si), the rare earth elements, hafnium (Hf), germanium (Ge), tin (Sn) and zirconium (Zr). The disk may be formed by co-sputtering the cobalt alloy material and the impurity element(s), and thereafter oxidizing the impurity element(s). The oxidation may occur by heating the disk while the magnetic layer is exposed to oxygen or air, or by exposure of the magnetic layer to an argon-oxygen plasma.
摘要:
An improved thin film magnetoresistive (MR) sensor uses an alloy comprising Fe, Mn and Cr as an antiferromagnetic layer to provide a longitudinal exchange bias in the ferromagnetic MR layer. Sufficient exchange biasing is provided and the FeMnCr layer exhibits excellent corrosion resistance.
摘要:
A thin film alloy disk for vertical magnetic recording has a cobalt-chromium-tantalum (CoCrTa) magnetic layer with perpendicular magnetic anisotropy deposited on an underlayer of beta-tantalum (.beta.-Ta). The .beta.-Ta layer is deposited on a suitable substrate, such as silicon, which is compatible with the formation of the beta phase of tantalum. The highly preferred orientation of the .beta.-Ta film on the substrate and the incorporation of Ta in the magnetic film results in the magnetic film having improved perpendicular magnetic anisotropy, high perpendicular coercivity and low horizontal coercivity. A nickel-iron (NiFe) layer may be deposited between the substrate and the .beta.-Ta underlayer to provide a magnetic flux return path.
摘要:
An electrically programmable read only memory assembly having cells arranged at the intersections of bit lines (BL1) and word lines (WL1, WL2), wherein each cell is formed of a bipolar transistor provided with a base region (70) and an emitter region (71) covered with a dielectric layer (2) made of an oxide or titanate of a transition metal. The cell in this condition represents a binary 0 information bit. The application of an appropriate voltage of approximately 4 volts to the pads of this cell through its corresponding bit line (BL1) and word line (WL2) causes the dielectric layer to break down and places the bit line in ohmic contact with the emitter, which sets the cell in its second condition representing a binary "1" information bit.
摘要:
A significantly thinner boron carbide overcoat layer is provided for a magnetic disk which has the same durability as thicker prior art overcoat layers for protecting an underlying magnetic layer. By employing adhesion layers selected from the group consisting of Ge, Ru, WTiSi, WTi, Si, and Y between the magnetic layer and the overcoat layer, the durability of the overcoat layer is significantly increased over a single overcoat layer of B4C. Certain process steps in the making of the B4C overcoat layer still further enhance the durability of the B4C overcoat layer by maintaining the disk or substrate specimen at a floating potential in a plasma chamber and employing low levels of argon pressure and sputtering wattage.
摘要:
A high-density recording media comprising longitudinally oriented polycrystalline barium ferrite exhibits large coercivity, corrosion resistance, high hardness and durability. Films are prepared by on-axis sputtering at ambient temperatures from stoichiometric targets followed by a post-deposition anneal at approximately 850.degree.C. to induce crystallization. Crystallization yields a magnetic film with large in-plane remanence and a fine scale texturing that greatly improves the tribological performance of barium ferrite disks. Exceptional durability can be achieved on disks without overcoats. Grain sizes as small as 200 .ANG. are produced by doping with small amounts of Cr.sub.2 O.sub.3 or other additives. Coercivities greater than 4000 Oe are achieved even in small grain films.
摘要翻译:包含纵向取向的多晶钡铁氧体的高密度记录介质具有较高的矫顽力,耐腐蚀性,高硬度和耐久性。 通过在环境温度下从化学计量的靶进行在轴溅射制备膜,然后在约850℃下进行后沉积退火以诱导结晶。 结晶产生具有大的面内剩余磁性膜和精细尺度纹理,大大提高钡铁氧体磁盘的摩擦学性能。 可以在没有大衣的磁盘上实现卓越的耐久性。 通过掺杂少量的Cr 2 O 3或其它添加剂来生产小于200安培的晶粒尺寸。 即使在小颗粒薄膜中也能获得大于4000 Oe的矫顽力。