Characterization of SWCNT Bundle Based VLSI Interconnect with Self-heating Induced Scatterings

Abstract

Performance of single walled carbon nanotube (SWCNT) bundle-based VLSI interconnects has been studied under the strong influence of scatterings induced by self-heating. Landauer Büttiker formalism along with Fourier heat transfer equation have been used to compute interconnect scattering parameters at various cross sectional areas of the interconnection. Cross sectional temperature calculation was performed using finite difference method considering temperature dependent thermal conductivity for primitive defect-less SWCNT bundles. Using the relaxation time approximation, we have studied scattering dynamics in calculating equivalent resistance. Electronic and thermal transport equations have been coupled and solved iteratively to get accurate estimation of temperatures and resistances. Study of scattering parameters shows low backscattering however significant transmission loss. Below 100GHz, for a 1µm long interconnect with 10 nm by10 nm cross sectional area shows S 21 as high as 80dB. In terahertz regime transmission parameter S 21 is in the range of few hundreds dB.

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