Method of manufacturing a disk drive head gimbal assembly having a flexure tail with folded bond pads
View Patent ↗A method to manufacture a head stack assembly for a disk drive, the method comprising: attaching a head gimbal assembly that includes a flexure tail having flexure bond pads to an actuator that includes a flexible printed circuit (FPC) with FPC bond pads; folding each of the flexure bond pads upon itself such that the flexure tail is substantially thicker at each of the folded flexure bond pads; aligning the flexure bond pads with the FPC bond pads; introducing an adhesive material that includes electrically conductive beads of substantially similar size between each of the flexure bond pads and corresponding ones of the FPC bond pads; and bringing a thermode tool into contact with the flexure bond pads after folding, with the thermode tool pressing the flexure bond pads against the FPC bond pads for a period.
1. A method to manufacture a head stack assembly for a disk drive, the method comprising:
attaching a head gimbal assembly that includes a flexure tail having a plurality of flexure bond pads to an actuator that includes a flexible printed circuit (FPC) with a plurality of FPC bond pads;
folding each of the plurality of flexure bond pads upon itself such that the flexure tail is substantially thicker at each of the folded flexure bond pads;
aligning the plurality of flexure bond pads with the plurality of FPC bond pads;
introducing an adhesive material that includes a plurality of electrically conductive beads of substantially similar size between each of the plurality of flexure bond pads and corresponding ones of the plurality of FPC bond pads; and
bringing a thermode tool into contact with the plurality of flexure bond pads after folding, with the thermode tool pressing the plurality of flexure bond pads against the plurality of FPC bond pads for a period.
2. The method of claim 1 wherein the flexure tail comprises a structural layer, a dielectric layer, and a conductive layer, and wherein a thickness of the structural layer is less than 20 microns, a thickness of the dielectric layer is less than 15 microns, a thickness of the conductive layer is less than 15 microns, and a total folded thickness at each of the plurality of flexure bond pads is at least 60 microns.
3. The method of claim 1 wherein pressing the plurality of flexure bond pads against the plurality of FPC bond pads during the period arranges the plurality of electrically conductive beads in a monolayer with each of the plurality of electrically conductive beads in electrical contact with one of the plurality of flexure bond pads and the corresponding one of the plurality of FPC bond pads.
4. The method of claim 1 wherein the thermode tool includes a flat surface that is substantially larger than any of the plurality of flexure bond pads.
5. The method of claim 1 wherein the thermode tool transfers heat through the plurality of flexure bond pads during the period, and raises the temperature of the adhesive material during the period.
6. The method of claim 1 wherein folding precedes aligning the plurality of flexure bond pads.
7. The method of claim 1 wherein aligning the plurality of flexure bond pads precedes folding.
8. The method of claim 1 wherein introducing the adhesive material comprises depositing the adhesive material on to the plurality of FPC bond pads prior to aligning the plurality of flexure bond pads.
9. The method of claim 1 wherein introducing the adhesive material comprises depositing the adhesive material on to a first side of the plurality of flexure bond pads after folding and prior to bringing the thermode tool into contact with an opposing second side of the plurality of flexure bond pads.
10. The method of claim 1 wherein folding each of the plurality of flexure bond pads upon itself comprises simultaneously folding all of the plurality of flexure bond pads by folding a terminal region of the flexure tail upon itself.