Interconnect processes

Which set correctly lists the main properties required of LSI wiring materials?

  1. ANot conducting electricity and not conducting heat
  2. BLow resistance, resistance to current-induced degradation (electromigration) and ease of processing
  3. CTransmitting light well and being soft
Show answer and explanation

Answer: B. Low resistance, resistance to current-induced degradation (electromigration) and ease of processing

Wiring materials need low resistance to reduce signal delay and power loss, reliability against degradation even at high current densities, and ease of patterning and filling fine features. Balancing these has driven the change from Al to Cu and, in the finest features, to other metals.

  • A. A material that does not conduct cannot be wiring.
  • B. Correct. Low resistance, reliability and processability are required.
  • C. Transmitting light is not required of wiring.
Practice this topic Back to topic

More Interconnect processes questions

  1. What is the basic role of the interlayer dielectric that fills the space between wires?
  2. Why has an Al-Cu alloy with about 0.5% copper been used for aluminum wiring?
  3. What is the phenomenon called in which electroplated Cu films, simply left at room temperature, grow larger grains over time and drop in resistivity?
  4. What is the main purpose of the design practice of placing two or more vias, rather than one, wherever possible to connect upper and lower wires?
  5. Which term refers to the contacts and local interconnects that connect the transistors to the multilevel wiring?