Method for bonding substrates in an energy assisted magnetic recording head
View Patent ↗A method for bonding a first substrate to a second substrate is described. The first substrate includes a first plurality of solder pads, a first alignment mark set, and a first plurality of dots. The second substrate includes a second plurality of solder pads, a second alignment mark set, and a second plurality of dots configured to interlock with the first plurality of dots. The method includes aligning the first alignment mark set with the second alignment mark set. The first alignment mark sets being aligned corresponds to the dots and the solder pads being aligned. The method also includes locking the first plurality of dots with the second plurality of dots to form an interlocking key. The method also includes reflowing at least one of the first and second pluralities of solder pads. The dots remain substantially solid during the reflow.
1. A method for performing bonding of a first substrate to a second substrate, the first substrate including a first plurality of solder pads and a first alignment mark set, the second substrate including a second plurality of solder pads and a second alignment mark set, the method comprising:
aligning the first alignment mark set on the first substrate to the second alignment mark set on the second substrate, the first substrate including a first plurality of dots, the second substrate including a second plurality of dots configured to interlock with the first plurality of dots, the first alignment mark set being aligned with the second alignment mark set corresponding to the first plurality of dots being aligned with the second plurality of dots and the first plurality of solder pads being aligned with the second plurality of solder pads;
locking the first plurality of dots with the second plurality of dots to form an interlocking key; and
reflowing at least one of the first plurality of solder pads and the second plurality of solder pads, the first plurality of dots and the second plurality of dots remaining substantially solid during the reflowing step.
2. The method of claim 1 wherein the first plurality of dots and the second plurality of dots include at least one of Au, Cu, Ni, and NiFe.
3. The method of claim 1 wherein the aligning step further includes:
aligning the first alignment mark set to the second alignment mark set to within 0.5 micron.
4. The method of claim 1 wherein the each of the first plurality of dots has at least one of a substantially circular cross-section, a substantially rectangular cross-section, and a re-entrant cross-section.
5. The method of claim 1 wherein the each of the second plurality of dots has at least one of substantially circular cross-section, a substantially rectangular cross-section, and a re-entrant cross-section.
6. The method of claim 1 wherein the each of at least a portion of the first plurality of dots is tapered.
7. The method of claim 1 wherein the each of at least a portion of the second plurality of dots is tapered.
8. The method of claim 1 wherein the locking step further includes:
pressing the first substrate against the second substrate.
9. The method of claim 1 wherein the first alignment mark set includes at least one male feature and the second alignment mark set includes at least one female feature corresponding to the at least one male feature.
10. The method of claim 9 wherein the first alignment mark set includes a cross pattern.
11. The method of claim 1 wherein the interlocking key locks the first plurality of dots with the second plurality of dots such that the first substrate remains within a desired tolerance with respect to the second substrate during the reflow step.
12. The method of claim 1 wherein the first plurality of dots and the second plurality of dots are configured to form a bond in the locking step.
13. The method of claim 1 wherein the first substrate includes a laser substrate and the second substrate includes a slider.
14. A method for performing bonding of a laser substrate to a slider, the laser substrate including a first plurality of solder pads and a first alignment mark set, the slider including a second plurality of solder pads and a second alignment mark set, the method comprising:
aligning the first alignment mark set on the laser substrate to the second alignment mark set on the slider to within 0.5 micron, the laser substrate including a first plurality of dots, the slider including a second plurality of dots configured to interlock with the first plurality of dots, the first alignment mark set being aligned with the second alignment mark set corresponding to the first plurality of dots being aligned with the second plurality of dots and the first plurality of solder pads being aligned with the second plurality of solder pads, the first alignment mark set including a first cross pattern, the second alignment mark set including a second cross pattern configured to interlock with the first cross pattern;
locking the first plurality of dots with the second plurality of dots to form an interlocking key such that the laser substrate remains within a 0.5 micron tolerance with respect to the slider during a reflow step and such that the first plurality of dots is bonded with the second plurality of dots; and
reflowing at least one of the first plurality of solder pads and the second plurality of solder pads, the interlocking key remaining substantially solid during the step of reflowing.