Packaging and assembly

In wire bonding, what is the main reason gold (Au) wire has been increasingly replaced by copper (Cu) wire?

  1. ABecause copper oxidizes less readily than gold
  2. BBecause copper is softer than gold and easier to bond
  3. CBecause material cost can be cut greatly, and its electrical conductivity is also good
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Answer: C. Because material cost can be cut greatly, and its electrical conductivity is also good

With the soaring price of gold, replacement with cheaper copper wire advanced. Copper also has excellent electrical and thermal conductivity. On the other hand, it is harder than gold and oxidizes easily, so measures are needed such as preventing chip damage during bonding and bonding in an inert gas atmosphere.

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