Abstract: A multi-layer circuit such as for a disk drive suspension has two regions: a supported region in which first and second stacked signal conductors are supported on a stainless steel support layer and an insulating layer, and an unsupported region having flying leads in which the flying leads are not supported below by the support layer. The two stacked signal conductors are formed by two separate plating operations, the two plating operations simultaneously creating the flying leads and the unsupported portions of the signal conductors, such that the flying leads have thicknesses that are the sum of the thicknesses of the individual conductors. Crossbars and vias allow the different plating layers to be connected together. This construction allows the individual conductors to be relatively thin and flexible for good electrical and mechanical performance, while creating relatively thick flying leads that are resistant to handling damage.

Abstract: For decreased pitch and roll stiffness, a ring gimbal suspension for a hard disk drive has torsion arms that extend toward the distal end of the suspension as they extend inward from the gimbal outer arms toward the slider bond pad. The torsion arms connect to the slider bond pad at a location that is distal of the dimple contact point. The electrical circuit traces are generally free of stainless steel except where the circuit traces cross the torsion arms, at which point they are affixed to the torsion arms. The electrical circuit traces can include an outward meander away from the slider bond pad as the traces pass over the torsion arms, for additional reduction in stiffness.

Abstract: In a disk drive suspension circuit, in order to improve stability of the stable pitch static attitude (PSA) over changes in humidity, the suspended portion of the flexible circuit and/or the gimbal support arm are modified to change their response(s) to humidity. In one embodiment, hygroscopic material such as the material of the insulating layer are added to the stainless steel gimbal support arm, so that in response to humidity it bends in the opposite direction as the suspended portion of the circuit. In another embodiment, additional hygroscopic material is added to the circuit, and/or the polyimide insulating layer or the coverlayer are selectively removed, so that the net bend in the suspended portion of the circuit over humidity is reduced, ideally to a condition of zero or close to zero net bending.

Abstract: A disk drive suspension circuit has copper signal conductors connected by vias through an insulative layer to respective stainless steel flying leads. The stainless steel flying leads are activated and plated with one or more metals, with a final layer over the flying lead being a layer such as gold, suitable for bonding to form bond pads. The gold bond pads may be attached using thermosonic welding, solder ball bonding, or other suitable methods to an electrical component such as wires or a the disk drive's pre-amp circuit.

Abstract: An electrical interconnect and a method of making an electrical interconnect in which a conductor has been substantially plated with a first protective metal shell, such as nickel, and a second outer metal shell, such as gold, before a covercoat has been applied. Such an electrical interconnect can be characterized as having an even-thickness outer shell on both its terminal pads and underneath the covercoat adjacent to the terminal pads, without overhangs or gaps near the bottom of the covercoat caused by surface etching during production.

Abstract: A method of preparing an additive suspension circuit for a hard disk drive suspension includes electrodepositing an alloy of copper using an electrolytic bath containing copper sulfate, tin, iron, sulfuric acid, and hydrochloric acid, using pulsed current of about 10-45 amperes per square foot.

Abstract: A dual stage actuator (DSA) suspension has a single microactuator such as a PZT element on one side of central longitudinal axis of the suspension, and a pseudo symmetry structure formed or affixed on the other side of the central longitudinal axis opposite the PZT. The pseudo symmetry structure has mass and stiffness that mirrors the PZT, thus keeping the suspension mechanically balanced and symmetric about the longitudinal axis for improved suspension performance especially in a shock environment.

Abstract: A load beam having a bent rail, a suspension that includes the load beam, and a related method for manufacturing a load beam. The method includes providing the load beam before the bent rail is formed, and coining the load beam at a location where the bend will occur in the rail.

Abstract: A structure for a load beam used in hard disk drive devices includes an asymmetric structure. The load beam exhibits longitudinal asymmetry (i.e., is asymmetric along its long axis) in regard to the weight distribution, but has a center of mass that lies along its longitudinal axis due to the provisioning of counterbalancing features, such as the addition of material, the removal of material, or a combination of adding material and removing material, or the use of an asymmetrical damping layer.

Abstract: A support arm for use in a disc drive suspension includes an asymmetry that creates a vertical coupling in the support arm, i.e., a slight lateral movement of the support arm distal end to which a load beam is mounted in response to vibration-induced bending of the support arm. The vertical coupling in the support arm at least partially cancels out during arm bending any vertical coupling which has been designed into the coupling between the load beam and the support arm to reduce track misregistration during flow-induced vibrations of the disc surface. In this way, track misregistration during both flow-induced vibrations and during arm bending is reduced. In a preferred embodiment the asymmetry is created by at least one of a first notch along an inside top edge of the arm, and a second notch along a bottom outside edge of the arm.

Abstract: A baseplate that is configured to be included in a hard disk drive suspension assembly, and a related method for manufacturing the baseplate. The baseplate having a surface that has been coined to reduce any roughness that might have existed in a portion of the surface before the surface was coined.

Abstract: A microactuator assembly for a hard disk drive head suspension has an expandable base of stainless steel sheet material defining a negative lead affixed to the negative electrode on the bottom surface of a piezoelectric element, and a piece of stainless steel sheet material defining a positive lead attached to the positive electrode on the top surface of the piezoelectric element. The leads may be affixed directly to the piezoelectric element via conductive adhesive. The microactuator assembly can be assembled separately, and then laser welded into place on a suspension. A bond pad made of stainless steel sheet material extends from the flexible circuit, is electrically connected to the microactuator driving voltage conductor within the flexible circuit through a via, and is electrically isolated from the suspension substrate by an insulating film. The microactuator unit positive lead is mechanically and electrically connected to the bond pad via laser welding.

Abstract: A test assembly for a disk drive suspension head gimbal assembly includes a steel mount plate and a mount sub-plate of a material such as silicon carbide having a modulus of elasticity to density ratio that is significantly higher than the ratio for stainless steel. Preferably the mount plate and the mount sub-plate taken together have a first resonant shear frequency of greater than 50 KHz, which is generally greater than the frequency range of interest for testing head gimbal assemblies. The high modulus of elasticity to density ratio helps to ensure that any shear mode resonances of the test assembly occur at frequencies that are higher than the frequencies of interesting for head gimbal assembly shear resonance testing purposes.

Abstract: A dual-stage actuator disk drive suspension load beam has a recessed cavity formed in it into which the microactuator motor is partially or completely placed. The cavity may be formed by partially etching the load beam during the same etching process that creates the load beam from a sheet of stainless steel material. The partially etched load beam having a cavity for the microactuator motor has the advantages of a lower profile, improved inertial balancing of the suspension, and increased sway resonant frequency.

Abstract: A rotational, shear mode, piezoelectric motor is integrated with a suspension, head or head gimbal assembly (HGA) into a collocated, rotational, shear mode, piezoelectric micro-actuated suspension, head or head gimbal assembly (HGA) for use in disk drives and disk drive manufacturing equipment. When excited by a control voltage, the collocated, shear mode, piezoelectric micro-actuated HGA rotates the head enabling high frequency, high resolution track positioning of the read/write element. The motor is integrated with the head and flexure (collocation). The head rotates about a rotation axis that is ideally located at the center of mass of the head. A shear mode piezoelectric motor rotates the head. A collocated, rotational, shear mode, piezoelectric micro-actuated HGA has high stiffness, high frequency response, high positioning resolution, low mass and low internal vibration for improved tracking, increased track density and greater disk drive storage capacity.

Abstract: In a disk drive suspension, a gimbal is longitudinally moment-balanced about the dimple to improve shock performance by adding weight to one side of the gimbal and/or by removing weight from the other side of the gimbal, such that when the suspension experiences an operational shock the gimbal the gimbal tends to stay level with the disk surface and not pitch relative to the disk surface. The gimbal may be moment balanced by leaving or depositing on the suspension's limiter tab the same insulative material as is used to form the flexible circuit, by increasing the mass of the limiter tab, and/or by reducing the size of the detabs or the trailing edge, or by other means.

Abstract: A disk drive suspension with a bend-down tab which supports an outrigger lead. The bend-down tab extends laterally to the suspension and away from the slider, and can include tabs which are narrower than the electrical lead. The depth of the tab can be at least the depth of the outrigger lead, or deeper. The tab can be supported by and integrally formed with an elongate gimbal spring arm.

Abstract: A gimbal, a disk drive suspension that includes the gimbal, and a related method of manufacture, wherein the gimbal is configured to be coupled between a disk drive slider and a disk drive load beam. The gimbal includes a strut having a buss and a projection that is coupled to the buss. A combination of the projection and the buss define a gap.

Abstract: A method of designing a hard disk drive suspension swage hub geometry for an actuator arm having upper and lower suspensions attached thereto, includes using a finite element analysis model to simulate the effects of swaging the suspensions to the actuator arm, identifying relevant geometric parameters of the suspensions, for each suspensions performing a linear regression to fit an equation containing the geometric parameters to a normal force of the suspension to the actuator arm after swaging according to the fine element analysis, identifying a desired range of differences between the normal forces, using the desired difference range, and solving for values of geometric parameters to produce a set of target design parameters for the suspension swage hubs.

Abstract: A disk drive flexure has a pattern of voids in the ground plane in the area directly underneath the read and write bond pads, in order to adjust the respective impedances of the read and write bond pad pairs to match the impedances of the read and write transducers and the signal trace pairs to and from the transducers. The resulting impedance matched bond pads increase the effective signal bandwidth of the flexure and its electrical connections, decreasing the probability of error at high signal speeds and increasing the maximum data rate through the suspension.