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Figure 8: IBM’s test vehicle and demonstration. SOURCE: IBM [9]

Figure 9: Applied Materials patent: fan-out chip (bridge) first and face-up process. SOURCE: US PATENT 10,651,126
substrate is just a regular build-up the bridge is optional. Figure 8 shows the Intel’s and IBM’s rigid bridges are either
substrate with a cavity on top. demonstration by IBM [9]. embedded in, or are on an organic package
The challenges in IBM’s DBHi are: substrate. There is another class of rigid
The bonding assembly process of DBHi bridge, which is embedded in the fan-out
is very simple (Figure 7). First, bond the 1. Handling and bonding of a portion of EMC. On May 12, 2020, Applied Materials
Chip 1 and the bridge with nonconductive the tiny rigid bridge on a portion of the obtained US patent 10,651,126 (filed on
paste (NCP) and thermal compression large chiplet with very fine-pitch pads; December 8, 2017). The company’s design
bonding (TCB). Then, bond Chip 2 and 2. Dealing with a situation in which there embedded the bridge in EMC by the fan-out
the bridge with NCP and TCB. Those are more than one rigid bridge on a chip (bridge) first and die face-up process
steps are followed by placing the module chiplet; and (Figure 9). This could be the very first patent
(Chip 1 + bridge + Chip 2) on the organic 3. Dealing with a situation in which of a rigid bridge embedded in fan-out EMC.
substrate with a cavity and then going there are more than two chiplets on a On August 25, 2020, during TSMC’s
through the standard flip-chip reflow package substrate. Annual Technology Symposium, the
assembly process. The underfill under company announced its integrated fan-out

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