Packaging and assembly

What is the defect called in which bonding wires are pushed aside and deformed by the resin flow during molding?

  1. AWire sweep
  2. BElectromigration
  3. CBlooming
Show answer and explanation

Answer: A. Wire sweep

If the force of resin flowing in during molding pushes wires sideways, they may touch neighboring wires and short, or break. This is called wire sweep and is prevented by adjusting wire length and layout and the resin's viscosity and injection speed.

  • A. Correct. It is wire deformation caused by resin flow.
  • B. Electromigration is current-driven atomic migration.
  • C. Blooming is charge overflow in image sensors.
Practice this topic Back to topic

More Packaging and assembly questions

  1. What change occurs when the temperature of a molding compound exceeds its glass transition temperature (Tg)?
  2. 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?
  3. In dense assemblies such as smartphones, what is the purpose of forming a metal film on the package surface by sputtering or similar?
  4. In reflow, what is the defect called in which one end of a small part such as a chip resistor lifts up so the part stands on end?
  5. What is the defect called in which the force or ultrasound of wire bonding cracks the insulator or silicon beneath the bond pad?