Abstract: A microactuator assembly is formed by depositing PZT material over electrode gaps, the electrode gaps being defined by the spaces between interleaved fingers of metal that define alternating plus and minus electrodes. The PZT material is hardened and poled. The PZT material may be deposited and poled either as isolated islands of PZT material across respective electrode gaps, or as a continuous sheet of PZT material with localized areas of that material being poled and then activated. The individual PZT elements are arranged such that successive PZT elements extend in the same direction as across the electrode gaps. The resulting microactuator assembly acts in the d33 direction of the PZT elements. The electrodes have raised or recessed features such as ribs or castellations, with the PZT material mating with those features, thus anchoring the PZT material to the electrodes.

Abstract: A method of assembly a dual stage actuated suspension includes either applying an adhesive to a microactuator motor and then B-staging, it or applying an adhesive that has already been B-staged such as in film adhesive form, then assembling it to a microactuator and then finishing the adhesive cure. The method allows greater control over how much adhesive is used, and greater control over spread of that adhesive, than traditional liquid epoxy dispense methods. Additionally, a suspension is provided that has a wrap-around electrode such that both the driving voltage and the ground, which are normally connected at different sides of a PZT, can be connected at the same side of the PZT, thus simplifying electrical connections to the PZT.

Abstract: A PZT microactuator such as for use in a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT will be mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover all of the top of the PZT, or most of the top of the PZT with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further.

Abstract: A vibration damper for a suspension has two different viscoelastic layers and two different constraint layers. The two viscoelastic layers can be tailored to have different properties, including different viscosities and/or peak vibration frequency damping at different frequencies. The vibration damper exhibits improved vibration damping as compared to a single layer damper having the same overall thickness at critical frequencies.

Abstract: In a dual stage actuated suspension, conductive adhesive is both sandwiched between a microactuator and a grounded stainless steel layer of the suspension, and also extends at least partially onto a wrap-around portion of the microactuator's ground electrode. The conductive adhesive that extends onto the wrap-around portion of the electrode has an exposed edge for more complete exposure and curing during the cure step.

Abstract: A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.

Abstract: A piezoelectric actuator such as for a hard disk drive or other application has a restraining layer on its side that is opposite the side on which the PZT is mounted. The restraining layer is a stiff material. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. For simplicity of construction and assembly to the suspension, the PZT actuator may be a multi-layer PZT with the top layer being unpoled or otherwise inactive PZT material, and having a wrap-around electrode so that the actuator can be mechanically and electrically bonded to the suspension or other environment using a single adhesive dispense and cure step.

Abstract: A PZT microactuator such as for a hard disk drive is a multi-layer PZT in which a first layer of PZT material that is disposed away from the side of the microactuator that is bonded to the suspension, responds to an actuation voltage differently than does a second layer of PZT material that is closer to the suspension, thus acting as a constraining layer and thus increasing stroke sensitivity of the microactuator. The first layer of PZT material can be made to respond differently than the second layer by not being activated, by being thicker that the second layer, or by being reverse poled as compared to the second layer. The effective stroke length of the microactuator is increased by the presence and effect of constraining layer.

Abstract: An electrical circuit for a disk drive suspension has a first signal trace above a grounded support layer which is typically stainless steel, and a second signal trace below the support layer, the two signal traces typically being opposite polarities of a differential signal pair. The support layer between the two signal traces is windowed, and the two traces are physically separated by a distance that equals the nominal thickness of the support layer plus the thicknesses of the top and bottom dielectric layers that separate the signal traces from the support layer. The physical separation combined with the windowing reduces the impedance and increases the bandwidth of the differential pair. The impedance can be controlled by the percentage of windowing in the support layer.

Abstract: A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer may extend beyond the edge of the PZT to define an overhang, with the electrical connection being made by bonding to the underside of the overhang thus reducing and controlling the height of the assembly.

Abstract: A dual stage actuated suspension has microactuators that are adhered to the suspension by adhesive such as epoxy. The epoxy is contained within an adhesive containment vessel defined by walls of an insulating material such as polyimide. Adhesive overflow channels are formed within the polyimide to receive and channel any excess epoxy that overflows over the polyimide wall. The channels may have increasing width to help draw the excess epoxy toward a centrally located reservoir.

Abstract: A PZT grounding connection to the stainless steel substrate of a suspension flexure includes an oversized void or via in the insulating layer of the flexure, copper being plated onto the stainless steel within the void with an intermediate layer of nickel therebetween, and conductive adhesive electrically and mechanically bonding the copper within the void to the PZT. The connection provides a high quality, low resistance ground path from the PZT to the stainless steel substrate without plating gold onto the stainless steel.

Abstract: In a dual stage actuated suspension, the conductive adhesive that forms the ground connection bridge from the ground electrode of the PZT microactuator to the grounded stainless steel layer of the flexure, extends from the ground electrode of the PZT around an edge of the stainless steel layer and to a side of the stainless steel layer that is opposite the side of the stainless steel layer to which the PZT is mounted. An aperture in the load beam allows a stream of hot air during the epoxy cure step to be directed directly onto the conductive epoxy ground connection bridge, thus allowing that conductive epoxy ground connection to be reliably and completely cured.

Abstract: In an electrical connection to an electrical component in a disk drive suspension, an electrical lead is adhered to a component using conductive adhesive and is also mechanically pressed up against the component using a bias mechanism. The bias mechanism may be a spring finger that is welded to the suspension, or it may be a stainless steel finger that is formed integrally with the trace gimbal assembly. The resulting bias force that presses the contact against the component surface reduces the small failure rate that can occur when the conductive adhesive separates from the component's surface as a result of stress such as induced by thermal cycling.

Abstract: A PZT limiter in a microactuator type dual stage actuated (DSA) suspension limits travel of the PZT, particularly of the cantilevered end of the PZT and particularly during non-operational shock. The PZT limiter thus limits the stresses including bending placed on the PZT during the shock event and thus helps to prevent cracking of the PZT. Additionally, by limiting displacement of the PZT, the limiter improves the mechanic and electrical performance of the suspension during operation.

Abstract: A dual stage actuated (DSA) suspension includes two PZT microactuators that are attached at their first ends to a non-gimbaled portion of the suspension, and are attached at their second ends to the gimbaled portion of the suspension such as the gimbal tongue through flexible connectors that can be formed integrally with the suspension's flexure. The flexible connectors are flexible enough so as not to interfere with the suspension's gimballing action. The flexible connectors transmit force from the PZTs to the gimbal as the PZTs expand and contract in order to rotate the gimbal and thus effect fine movements of the head slider. The flexible connectors are positioned laterally outwardly of the leading edge of the slider, thereby protecting both the connectors and the PZTs from damage induced by the slider striking the connectors during a shock event.

Abstract: In an electrical connection to a microactuator in a disk drive suspension, an electrical lead is adhered to a microactuator using conductive adhesive and is also mechanically pressed up against the microactuator using a bias mechanism. The bias mechanism may be a spring finger that is welded to the suspension, or it may be a stainless steel finger that is formed integrally with the trace gimbal assembly. The resulting bias force that presses the contact against the microactuator surface reduces the small failure rate that can occur when the conductive adhesive separates from the microactuator's surface as a result of stress such as induced by thermal cycling.

Abstract: A dual stage actuated (DSA) suspension includes two PZT microactuators that are attached at their first ends to a non-gimbaled portion of the suspension such as the portion of the flexure that is rigidly attached to the load beam, and are attached at their second ends to the gimbaled portion of the suspension such as the gimbal tongue through flexible connectors that can be formed integrally with the suspension's flexure. The flexible connectors are flexible enough so as not to interfere with the suspension's gimballing action. The flexible connectors transmit force from the PZTs to the gimbal as the PZTs expand and contract in order to rotate the gimbal and thus effect fine movements of the head slider.

Abstract: A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover all of the top of the PZT, or most of the top of the PZT with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further.

Abstract: A stainless steel suspension component such as a mount plate is chemically activated by exposure to an activating solution. Gold is then spot plated onto the mount plate in the activated area using an elastomeric mask that is clamped over the mount plate. A component may then be bonded to the gold bond pads. The component may include a PZT microactuator bonded to the gold bond pads using a conductive adhesive such as silver epoxy. The gold acts as an interface metal that provides to a low resistance and environmentally robust ground path for the microactuator.