Packaging and assembly

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?

  1. ADicing before grinding (DBG)
  2. BStepper exposure
  3. CThe CZ method
Show answer and explanation

Answer: A. Dicing before grinding (DBG)

In DBG, grooves slightly deeper than the final thickness are first cut from the front of the wafer; grinding the back then separates the chips once the grooves are reached. Compared with cutting an already-thinned wafer, this reduces cracking and chipping, so it is used for thin chips such as those stacked in memory packages.

  • A. Correct. Grooves are cut first, then the back is ground to separate chips.
  • B. Stepper exposure prints patterns.
  • C. The CZ method pulls single crystals.
Practice this topic Back to topic

More Packaging and assembly questions

  1. In dense assemblies such as smartphones, what is the purpose of forming a metal film on the package surface by sputtering or similar?
  2. 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?
  3. What is the defect called in which the force or ultrasound of wire bonding cracks the insulator or silicon beneath the bond pad?
  4. Which correctly describes wire bonding?
  5. Which correctly describes flip-chip mounting?