Packaging and assembly

In wire bonding that forms a ball, where is the first bond (ball bond) generally made?

  1. AOn the surface of the molding compound
  2. BOn the chip's bond pad
  3. COn the leadframe or package substrate
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Answer: B. On the chip's bond pad

In ball bonding, the ball formed at the wire tip is first bonded to the chip's pad (first bond), then the wire is looped over and pressed flat onto the lead or substrate electrode (second bond). The ball bond is small, suiting the chip's narrow pads.

  • A. Nothing is bonded to the molding compound surface.
  • B. Correct. The ball is first bonded to the chip pad.
  • C. The lead or substrate side is the second bond.
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More Packaging and assembly questions

  1. What is the main purpose of heating packages in an oven for some time after molding (post-mold cure)?
  2. What is the defect called in which bonding wires are pushed aside and deformed by the resin flow during molding?
  3. What change occurs when the temperature of a molding compound exceeds its glass transition temperature (Tg)?
  4. Which method makes very thin chips by first cutting grooves partway into the wafer from the front and then grinding the back to separate the chips?
  5. In dense assemblies such as smartphones, what is the purpose of forming a metal film on the package surface by sputtering or similar?