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possible accuracy. Accuracy is automatically
tweaked by occasional recalibrations using
glass scales at the edge of the bondable area.
An electronic vibration cancellation system
ensures that vibrations do not interfere with
placement accuracy, and settling times are
very short.
Figure 4 shows typical accuracy results
measured by placing glass die and then using
an in situ post-place inspection to assess the
accuracy of the placements—in this case,
over a period of five hours. All data points are
within ±3µm, and one should also note the
tight grouping of the means of each nozzle (red
dots in Figure 4).

Table 3: Application changeover.

Co-planarity of nozzles inspected by the engineer to verify uniform
Both fluxing and placing of the die requires flux coverage of all of the bumps.
that the die touch down on the surface with
a high degree of planarity so that the die Figure 4: Accuracy over a 5-hour run verified by
becomes evenly fluxed and solder bumps post-place inspection of glass die placements. The red
don’t become deformed by a tilted touchdown dots represent the mean for each of the 12 nozzles.
that puts all of the force on just a few bumps.
Reasonable ease of use in a multi-placer
system then requires that there be only one Summary
calibration/adjustment per bond head for this We have realized an advanced FC
planarity and that all six place nozzles on bonder that can achieve up to 15K UPH and
that bond head are already coplanar from the 5μm accuracy for cost-effective bonding
factory and will not change over time. This of routine and advanced flip-chip mass
goal was achieved through a very thoughtful reflow packages. With the ability to place
Z-bearing system design, tight manufacturing at 3μm accuracy with only minor reduction
specifications, and careful manufacturing Figure 3: A typical flux imprint. in throughput, the bonder also meets the
quality control. Since each nozzle can move needs for advances in FC mass reflow
independently in Z under pneumatic control, Accuracy that are being pursued in R&D right now.
the requirement is only that the nozzles are As already mentioned, Katalyst™ can Through careful system design and ease
coplanar to each other. They do not all need achieve 5µm (3-sigma) accuracy at full speed of use features, this platform can achieve
to be on the exact same plane. and 3µm (3-sigma) accuracy at a nominally this throughput in a practical manner in a
Coplanarity of the nozzles to the fluxer is reduced speed. The basic alignment is production environment and with relatively
verified at each application changeover and accomplished by a down-looking camera frequent product changeover.
whenever an engineer desires by the use of a on the bond head for finding the substrate
semi-automatic flux imprint test. For this test, fiducials and an up-looking camera for References
the bonder will dip a die into the flux, place locating the die on the placers. The two 1. “Die Attach Equipment Market Report
it onto a substrate or other surface and take cameras are aligned with each other in an 2019,” Yole Développement, 2019.
an image (Figure 3). This image can then be automatic calibration to achieve the best

Biography
Horst Clauberg is Director, AP Process Engineering, at Kulicke & Soffa Industries Inc., Fort Washington,
PA. He leads both the Process and Field Applications Engineering groups in the Advanced Packaging BU,
which includes flip-chip, thermocompression, and die bonders. He has served in various R&D roles during his
nearly 20 years with Kulicke & Soffa Ind. and holds a PhD in Physical Chemistry from Harvard U.; he is an
inventor on more than 20 U.S. patents. Email hclauberg@kns.com

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