Interconnect processes

Which statement about the capacitance of a wire is correct?

  1. AOnly the capacitance to adjacent wires in the same layer needs to be considered
  2. BIn addition to capacitance to adjacent wires in the same layer, there is capacitance to wires in layers above and below and to the substrate
  3. CWires have no capacitance
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Answer: B. In addition to capacitance to adjacent wires in the same layer, there is capacitance to wires in layers above and below and to the substrate

A wire's capacitance combines the lateral capacitance to adjacent wires in the same layer and the vertical capacitance to wires in layers above and below and to the substrate. As wiring pitch tightens, the lateral share grows.

  • A. Capacitance to layers above and below and to the substrate cannot be ignored.
  • B. Correct. There are both lateral and vertical components.
  • C. Wires always have capacitance to surrounding conductors.
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More Interconnect processes questions

  1. What is the effect of increasing a wire's thickness (height) without changing its width?
  2. In chips using mechanically weak low-k films, what is the problem called in which stress during packaging cracks or delaminates the films?
  3. What film is commonly placed on top of Cu wiring to act both as a diffusion barrier toward the dielectric and as an etch stop?
  4. In electromigration testing, wires shorter than a certain length show greatly extended lifetimes, with almost no degradation. What is this phenomenon called?
  5. When a wire becomes narrower than its grains so that grain boundaries line up across the wire, what is this structure called, and how does it affect electromigration?