摘要:
A MR sensor is disclosed that has a free layer (FL) with perpendicular magnetic anisotropy (PMA) which eliminates the need for an adjacent hard bias structure to stabilize free layer magnetization and minimizes shield-FL interactions. In a TMR embodiment, a seed layer, free layer, junction layer, reference layer, and pinning layer are sequentially formed on a bottom shield. After patterning, a conformal insulation layer is formed along the sensor sidewall. Thereafter, a top shield is formed on the insulation layer and includes side shields that are separated from the FL by a narrow read gap. The sensor is scalable to widths
摘要:
A MR sensor is disclosed that has a free layer (FL) with perpendicular magnetic anisotropy (PMA) which eliminates the need for an adjacent hard bias structure to stabilize free layer magnetization and minimizes shield-FL interactions. In a TMR embodiment, a seed layer, free layer, junction layer, reference layer, and pinning layer are sequentially formed on a bottom shield. After patterning, a conformal insulation layer is formed along the sensor sidewall. Thereafter, a top shield is formed on the insulation layer and includes side shields that are separated from the FL by a narrow read gap. The sensor is scalable to widths
摘要:
A track shield structure is disclosed that enables higher track density to be achieved in a patterned track medium without increasing adjacent track erasure and side reading. This is accomplished by placing a soft magnetic shielding structure in the space that is present between the tracks in the patterned medium. A process for manufacturing the added shielding structure is also described.
摘要:
A CPP MR sensor interposes a tapered soft magnetic flux guide (FG) layer between a hard magnetic biasing layer (HB) and the free layer of the sensor stack. The flux guide channels the flux of the hard magnetic biasing layer to effectively bias the free layer, while eliminating instability problems associated with magnetostatic coupling between the hard bias layers and the upper and lower shields surrounding the sensor when the reader-shield-spacing (RSS) is small.
摘要:
A method of forming a hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed. A HB layer is formed with easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield is deposited on the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading.
摘要:
A spin transfer oscillator with a seed/SIL/spacer/FGL/capping configuration is disclosed with a composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (A1/A2)X laminated spin injection layer (SIL). Field generation layer (FGL) is made of a high Bs material such FeCo. Alternatively, the STO has a seed/FGL/spacer/SIL/capping configuration. The SIL may include a FeCo layer that is exchanged coupled with the (A1/A2)X laminate (x is 5 to 50) to improve robustness. The FGL may include an (A1/A2)Y laminate (y=5 to 30) exchange coupled with the high Bs layer to enable easier oscillations. A1 may be one of Co, CoFe, or CoFeR where R is a metal, and A2 is one of Ni, NiCo, or NiFe. The STO may be formed between a main pole and trailing shield in a write head.
摘要:
A PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing through an AFM-FM phase change material that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be comprised of a laminated structure having a plurality of “n” ferromagnetic layers and “n-1” AFM-FM phase change material layers arranged in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content >35 atomic %. AFM-FM phase change material may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip. Heating for the AFM to FM transition is provided by write coils and/or a coil located near the AFM-FM phase change material to enable faster transition times.
摘要:
A method of manufacturing a PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing by including an AFM-FM phase change material spacer that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be formed as a laminated structure by a sputter deposition process wherein a plurality of “n” ferromagnetic layers and “n−1” AFM-FM phase change material layers are laid down in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content >35 atomic %, and may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip.
摘要:
A spin transfer (torque) oscillator (STO) with a non-magnetic spacer formed between a spin injection layer (SIL) and a field generation layer (FGL), and with an interfacial layer comprised of Fe(100-V)CoV where v is from 5 to 100 atomic % formed between the SIL and non-magnetic spacer is disclosed. A composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture is used to enhance perpendicular magnetic anisotropy (PMA) in the STO device. The interfacial layer quenches SIL oscillations and thereby stabilizes the SIL against FGL oscillations. The interfacial layer preferably has a thickness from 5 to 50 Angstroms and enhances amplitude (dR/R) in the STO device. The STO device may have a top SIL or bottom SIL configuration. The SIL is typically a laminated structure such as (Co/Ni)X where x is between 5 and 50.
摘要:
A spin transfer oscillator (STO) device is disclosed with a giant magnetoresistive (GMR) junction comprising a magnetic resistance layer (MRL)/spacer/magnetic oscillation layer (MOL) configuration, and a MR sensor including a sensing layer/junction layer/reference layer configuration. MOL and sensing layer are magnetostatically coupled and separated by a conductive spacer. MRL has perpendicular magnetic anisotropy while MOL and sensing layer have a Mst (saturation magnetization×thickness) value within ±50% of each other. When a magnetic field is applied perpendicular to the planes of the MOL and a high density current flows from the conductive spacer to the MRL, a MOL oscillation state with a certain frequency is induced. Consequently, the sensing layer oscillates with a similar RF frequency and when a low density current flows across the MR sensor, an AC voltage signal is generated to determine the sensing layer frequency that can be varied by adjusting the applied field.