An Air-Corridor Interconnect Structure
Jemin Park and Chenming Hu
Samsung and ERSO Chair fund
We propose a novel mostly-air interconnect structure. Every metal line is surrounded by an air arch on the sides and overhead. It is supported on the bottom by a series of solid dielectric beams. The vias are also surrounded by air sheaths. The arch of an air gap not only has lower effective capacitance but also higher stability of structure. Raphael simulation shows that the total capacitance is reduced by about 45% and the RC delay is decreased about 55%. The effective dielectric constant can be reduced to about 1.7 using existing dielectric with k = 2.9.
Figure 1: 3D structures of our BEOL process with air gap: (a) tilt view of the structure; (b) front view of the structure; and (c) side view of the structure
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