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Figure 2: Various approaches of accomplishing heterogeneous integration (HI). SOURCE: ASMPT internal report, 2019
last/face-down mode, which is important Multi-die requirement. As HI Thin-die requirement. Because the
for high-density fan-out applications. In continues to prevail, multi-die packages package profile is another essential factor
the case of thermocompression bonding containing dies of different sizes will when considering AP, sometimes die
(TCB), flip-chip bonding with local reflow become common (Figure 5). The die thickness would go down below 50μm.
is a must requirement, though typically, it attach tool should be able to support a For some specific applications, such
cannot co-exist with fan-out bond modes. single recipe to handle different die sizes. as memory die for stacking, as well as
Die size. Because of the varying die Hardware support required includes tooling bridge die for embedding, the thickness
sizes required for different processes, the designed for different die sizes and the could be as thin as, or less than, 30µm.
range of die sizes can vary from 0.5mm x tooling such as the ejector, die pick collet, Normal pin for die ejection might
0.5mm to a size as large as 26mm x 33mm. and die bond collet should be automatically become insufficient to ensure crack-free
The size of molded compound die can be changed. Additionally, wafers of different die pick-up; specially designed needle-
up to 70mm x 70mm. It is a challenge for dies should be automatically loaded from less multi-blade ejector technology
a die attach tool to allow such a large die the wafer cassette, without the need for has been proven to be a high-volume
size variation from pick-up until the attach human intervention to support tooling part manufacturing (HVM) solution for thin-
process on the substrate is complete. conversion and recipe program loading. die handling (Figure 6).

Figure 3: Examples of major advanced packaging and placement accuracy requirements.

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