Emerging Interconnect Technologies 189
to grow vertically from the catalyst layer Fe on the bottom wafer. By using
thermal chemical vapor deposition technique, the authors have demonstrated
the capability of growing aligned carbon nanotube bundles with an average
length of 140 μmandadiameterof30μm from the through holes.
5.6.3 Optical TSVs
Optical TSV could empower an enormous bandwidth increases, increased
immunity to electromagnetic noise, a decrease in power consumption, syn-
chronous operation within the circuit and with other circuits, and reduced im-
munity to temperature variations. The constraints for developing optical TSVs
are the fact that all the fabrication steps have to be compatible with future
IC technology and that the additional cost ...