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: 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: 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.

Abstract: A low impedance, low crosstalk disk drive suspension circuit has multiple traces carrying a first polarity of a differential signal, interleaved with multiple traces carrying the second polarity of a differential signal. Each pair of conductors consisting of a trace of the first polarity and a trace of the second polarity may cross over each other at multiple crossover points. The crossover connections may utilize a second layer of copper trace conductors over the first and main layer, or alternatively the crossover connections may utilize an isolated portion of the suspension substrate.

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.

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 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: An electrical interconnect from a suspension electrical circuit to a PZT microactuator motor includes copper plated onto a first side of a stainless steel support layer and gold plated onto a second and opposite side of the stainless steel support layer, with the gold plated stainless steel surface bonded to the PZT motor surface by conductive epoxy. The stainless steel may have a via etched into it to the copper surface before the gold plating step which then plates both the stainless steel and the copper with gold, so that the conductive epoxy is in physical and electrical contact with both the gold plated stainless steel and thus in electrical contact with the copper, and also in direct physical and electrical contact with the gold plated copper.

Abstract: A PZT microactuator for a disk drive suspension has a first electrode on a majority of its top surface, a second electrode on a majority of its bottom surface, the first electrode extending to a small portion of the bottom surface through a via filled with a conductive material such as conductive epoxy. The microactuator may be cut near the via during manufacturing in order to separate it from the bulk PZT material. Alternatively, the microactuator may be cut through the via in which case the via becomes a conductive column at the side edge of the microactuator. The conductive column may be coated with an encapsulant in order to prevent particle shed from the cut material.

Abstract: A dual stage microactuated (DSA) suspension has two microactuators which are located approximately mid-load beam, and which are close to the stiffening edge rails of the load beam. A vertically extending C-spring is formed in the rails adjacent the microactuators in order to allow the microactuators to expand and contract.

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 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. The pseudo symmetry structure can include a spring to keep the PZT under compression to prevent PZT failure, and/or a strain gauge for use by the head positioning servo-control system.

Abstract: In a disk drive suspension circuit, an electrical contact from a flexible circuit to a face of a PZT microactuator is provided by a mechanical bias to press a contact pad of the flexible circuit against the PZT surface. The mechanical bias is provided by a piece of stainless steel that is welded to a nearby point or points on the suspension, and which biases the electrical contact pad carrying the PZT driving voltage against the PZT. The piece of stainless steel may be in the form of a flat piece welded on one or more sides of the contact pad, and may include a dimple for pressing against the contact pad. Additional insulation material may be provided between the dimple and the contact pad to prevent the dimple from penetrating through the flexible circuit's cover layer and shorting the driving voltage.

Abstract: A method is presented for creating multilayer bond pads for bonding a disk drive suspension circuit to a read-write head slider. The multilayer bond pads eliminate the need for vias to transition signals between metallization layers within a suspension circuit. The method includes the steps of forming an aperture through an insulating material that has a metalized first side, depositing a second metal layer on the second side and within the aperture, the second metal layer forming an electrical contact with the first metal layer, selectively removing portions of the second metal layer within the aperture and corresponding adjacent portions of the first metal layer thereby dividing the second metal layer and respectively adjacent portions of the first metal layer into a plurality of electrically separated circuit bond pads, each bond pad including respective portions of the first metal layer and respectively adjacent portions of the second metal layer.

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 low impedance, low crosstalk disk drive suspension circuit has multiple traces carrying a first polarity of a differential signal, interleaved with multiple traces carrying the second polarity of a differential signal. Each pair of conductors consisting of a trace of the first polarity and a trace of the second polarity may cross over each other at multiple crossover points. The crossover connections may utilize a second layer of copper trace conductors over the first and main layer, or alternatively the crossover connections may utilize an isolated portion of the suspension substrate.

Abstract: A dual stage actuated (DSA) suspension includes a dam-like structure that holds epoxy along the outside lateral side of the PZT microactuators while that epoxy hardens. In the illustrative embodiment, the dam-like structure is in the form of a wing rail that is integrally formed with the suspension base plate, and extends parallel to the outside face of the PZT. The wing rail has an upturned edge to help contain the epoxy while it hardens. The wing rail has springs at its fore and aft ends so that the rail does not unduly limit movement of the PZTs and hence microactuator stroke length. The wing rail does not touch the PZT electrodes. The encapsulation dam allows epoxy to be dispensed after the PZT has been located on the suspension, so as to substantially cover all sides of the PZT and thus prevent the shedding of contaminating particles during operation.

Abstract: In a dual stage actuated (DSA) suspension, a PZT microactuator is electrically and mechanically bonded to the rest of the suspension by non-conductive epoxy on the front and rear bottom faces of the PZT, by conductive epoxy that bridges a gap between the top face of the PZT which defines the ground electrode and an adjacent metallic and grounded portion of the suspension, and further by additional non-conductive epoxy that bridges the gap and which at least partly overlies the conductive epoxy. The additional non-conductive epoxy increases the effective stroke length of the PZT.