A stationary portion of a spindle motor includes a stator portion and an outside surface. The stator portion includes a stator core and coils. The outside surface extends in an axial direction parallel or substantially parallel to a central axis, and is centered on the central axis. The spindle motor includes a fixing portion at which an inside surface of the stator core and the outside surface are fixed to each other. The fixing portion includes a first press fit portion, a second press fit portion, and a gap arranged therein. The gap is located between the first press fit portion and the second press fit portion. The second press fit portion is located above the first press fit portion. At least a portion of the second press fit portion is located above a middle of the stator core in the axial direction.

A spindle motor includes a base, a shaft arranged on the base and extending in a vertical direction, a stator having a coil defined by a wound conductive wire and arranged on an upper surface of the base, and a rotor rotatably supported around the shaft. The base has a through hole that penetrates the base from the upper surface to a lower surface. The conductive wire is drawn out to the lower surface side through the inside of the through hole. The through hole is sealed by a sealing material. The through hole includes a columnar lower column body and a columnar upper column body. The lower column body is arranged on the lower surface side of the base. A cross-sectional area of the upper column body orthogonal to an axial direction is smaller than a cross-sectional area of the lower column body orthogonal to the axial direction.

A hard disk drive includes a base deck that is coupled to a cover, a motor assembly that is coupled to the base deck, and magnetic recording media that is coupled to the motor assembly. The motor assembly includes a magnetic bearing with a horizontal magnetic bearing component and a vertical magnetic bearing component.

A method for fabricating an improved magnetic tunneling junction (MTJ) structure is described. A bottom electrode is provided on a substrate. A MTJ stack is deposited on the bottom electrode. A top electrode is deposited on the MTJ stack. A first stress modulating layer is deposited between the bottom electrode and the MTJ stack, or a second stress modulating layer is deposited between the MTJ stack and the top electrode, or both a first stress modulating layer is deposited between the bottom electrode and the MTJ stack and a second stress modulating layer is deposited between the MTJ stack and the top electrode. The top electrode and MTJ stack are patterned and etched to form a MTJ device. The stress modulating layers reduce crystal growth defects and interfacial defects during annealing and improve the interface lattice epitaxy. This will improve device performance.

A motor includes a base, a bearing sleeve, a stator, a rotating member, a thrust bearing, and a hub. The bearing sleeve is arranged with the base and has an opening end and a sealing end opposite to each other. The stator connects with the base or the bearing sleeve. The rotating member is arranged inside the bearing sleeve and includes a shaft and a limiting portion adjacent to the sealing end. A first end of the shaft connects with the limiting portion, and a second end of the shaft has a coupling portion adjacent to the opening end. The thrust bearing is arranged between the shaft and an inner surface of the bearing sleeve, so that the limiting portion is between the thrust bearing and the sealing end. The hub connects with the coupling portion of the shaft and has a permanent magnet corresponding to the stator.

Aspects of the disclosure provide for mitigating a coefficient of thermal expansion (CTE) mismatch between glass components and adjacent metal components in a disk storage device to improve thermal and shock performance. The methods and apparatus provide a hub, provide a first recording disk comprising a glass material and a center hole on the hub such that the hub extends through the center hole of the first recording disk, provide a first spacer on the first recording disk, the first spacer comprising a nickel-iron alloy, and provide a second recording disk comprising a glass material and a center hole on the first spacer such that the hub extends through the center hole of the second recording disk, wherein the first recording disk and the second recording disk each comprise a magnetic recording layer configured to store information.

According to one embodiment, a disk device includes a housing with a bottom wall, magnetic disks supported on a hub of a motor, a printed circuit board provided on an outer surface of the bottom wall, and a wiring board attached on the outer surface of the bottom wall. The bottom wall includes a recess formed in the outer surface, a step located on border between the outer surface and the recess, and through holes opened to the recess. The wiring board includes one end portion disposed in the recess and connection pads on the one end portion, connected to lead wires of a coil. An adhesive is filled into the recess and the through holes, and covers the one end and a solder joint and seals the through holes.

The spindle motor includes; a shaft including a shaft portion and a flange portion, the shaft portion having a columnar shape extending in an axial direction, the shaft portion including a shaft end portion, the flange portion being provided at the shaft end portion and receiving a load in the axial direction; and a bearing sleeve rotatably supporting the shaft, the bearing sleeve having a tubular shape including a sleeve end portion having a large-diameter recess part formed in the axial direction. The shaft is a member formed of a copper alloy containing from 0.5 mass percent to 1.5 mass percent of silicon and from 0.5 mass percent to 3.0 mass percent of manganese, and the member includes the shaft portion and the flange portion integrated with one another.

Aspects of the disclosure provide for mitigating a coefficient of thermal expansion (CTE) mismatch between glass components and adjacent metal components in a disk storage device to improve thermal and shock performance. The methods and apparatus provide a hub, provide a first recording disk comprising a glass material and a center hole on the hub such that the hub extends through the center hole of the first recording disk, provide a first spacer on the first recording disk, the first spacer comprising a nickel-iron alloy, and provide a second recording disk comprising a glass material and a center hole on the first spacer such that the hub extends through the center hole of the second recording disk, wherein the first recording disk and the second recording disk each comprise a magnetic recording layer configured to store information.

A magnetic tunneling junction (MTJ) structure is described. The MJT structure includes a stress modulating layer on a first electrode layer, where a material of the stress modulating layer is different from a material of the first electrode layer. The MJT structure further includes a MTJ material stack on the stress modulating layer. And the MJT structure further includes a second electrode layer on the MTJ material stack. The stress modulating layer reduces crystal growth defects and interfacial defects during annealing and improve the interface lattice epitaxy. This will improve device performance.