Interconnect processes

Which correctly describes the damascene process commonly used to form copper wiring?

  1. ACopper film is patterned directly by dry etching
  2. BTrenches are formed in the insulator, filled with copper, and the excess copper is removed by CMP
  3. CCopper is thermally oxidized to form the wiring shape
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Answer: B. Trenches are formed in the insulator, filled with copper, and the excess copper is removed by CMP

In the damascene process, trenches shaped like the wiring are first etched into the insulator, barrier and seed layers are deposited, and copper is filled by plating. Finally, CMP removes the excess copper from the surface, leaving wiring only in the trenches. Filling trenches and vias at once is called the dual damascene process.

Forming copper wiring by damascene Insulator Barrier and seed Copper ① Etch trench ② Barrier/seed ③ Plate copper ④ CMP
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More Interconnect processes questions

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  2. What is the main purpose of barrier metals such as Ta and TaN in copper wiring?
  3. Which correctly describes a via in multilevel interconnects?
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