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 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: 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 method for transfecting a eukaryotic cell in which: a composition that includes at least one saccharide and at least one protein and optionally a salt and/or a pH-stabilizing component is contacted with a nucleic acid and a transfection reagent; a complex of nucleic acid and transfection reagent is formed by interaction with the composition; the complex is dried; the dried complex is stored for a period of time; after storing, the dried complex is taken up into a liquid; and the complex taken up into the liquid is transfected into the eukaryotic cell.

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 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 gimbal dual stage actuated suspension has a microactuator attached at its distal end to the gimbal in order to effect fine movements of the head slider. The microactuator is mounted on the side of the flexure that is opposite the disk platter and the head slider, and extends in height through an aperture in the load beam. The driving voltage for the microactuator is provided through an aperture in the insulating layer of the flexure to a signal conducting layer in the flexure's electrical circuit. The electrical connection from the signal conducting layer to the microactuator can comprise an electrically conductive adhesive, or an electrically conductive adhesive that contacts an isolated island of the stainless steel support layer in the flexure which is in electrical contact with the conducting layer, which is plated all the way to the stainless steel layer or which is otherwise extended thereto.

Abstract: A flexible electrical circuit such as for use in a hard disk drive dual stage actuated (DSA) suspension has a dimple or other raised feature such as a jog formed in an electrical contact pad. The dimple raises up at least part of the contact pad in height so as to reduce the distance that an electrical bridging component or material such conductive epoxy, solder paste, or jet dispensed solder must traverse in order to complete an electrical connection from the contact pad to an adjacent piezoelectric microactuator or other electrical component for which the electrical circuit carries an electrical signal or electrical power. The reduced distance improves the cleanliness and reliability of the electrical and physical bond, and can allow for electrical connection types that would otherwise be impractical.

Abstract: The present invention provides a novel RNAi based selection system for selecting host cells that have incorporated an expression vector.

Abstract: In a gimbal dual stage actuated suspension, the gimbal including the head slider is moment-balanced about the load beam dimple thus reducing sway mode gain. In a ring gimbal suspension the T-limiter can be removed and replaced with an extended gimbal tongue including the same layers of insulating material and copper that are part of flexure's flexible circuit, thus allowing the moment-balancer to be formed integrally with the rest of the flexure as part of the standard flexure manufacturing process. Additionally, the traces of the flexible circuit can be made to run at least partially underneath the head slider and approach the slider bond pads from the proximal side of the suspension, thereby shifting weight toward the proximal side.

Abstract: A PZT microactuator such as for a hard disk drive 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 microactuator 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 microactuator can be mechanically and electrically bonded to the suspension using a single adhesive dispense and cure step.

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. 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. Hygroscopic material such as the material of the insulating layer may be 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.