IC Assembly

Molded Underfill Flip-Chip Package


A molded underfill flip-chip package is a semiconductor package in which the narrow gap between IC chip and a substrate is filled with mold resin. Both filling the gap under the IC chip and the molding of the package are accomplished simultaneously.
This technology contributes to package size miniaturization and cost savings.


  • Mold resin incorporates fine filler and can even be used to fill gaps between IC chips and substrate that are 45 μm or less
  • Achieves smaller package size since no underfill dispense area is required
  • Both solder bumps and Cu pillars are available to use for this process
  • Low-alpha-ray mold resin is supported
  • Passive components can be built in. (Chip component size [mm]: 0402, 0603, 1005)





  • Various controller IC chips
  • Mixed mounting of multiple IC chips (MCP: Multi Chip Package)
  • BGA/LGA package mounted multiple IC chips and passive components