Contact resistance and reliability of 40 nm carbon nanotube vias

Moving beyond the limits of silicon transistors requires both a high-performance channel and high-quality electrical contacts. Carbon nanotubes provide high-performance channels below 10 nanometers, but as with silicon, the increase in contact resistance with decreasing size becomes a major performance roadblock. We report a single-walled carbon nanotube (SWNT) transistor technology with an end-bonded contact scheme that leads to size-independent contact resistance to overcome the scaling limits of conventional side-bonded or planar contact schemes. A high-performance SWNT transistor was fabricated with a sub–10-nanometer contact length, showing a device resistance below 36 kilohms and on-current above 15 microampere per tube. The p-type end-bonded contact, formed through the reaction of molybdenum with the SWNT to form carbide, also exhibited no Schottky barrier. This strategy promises high-performance SWNT transistors, enabling future ultimately scaled device technologies.

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Statistical latency analysis of carbon nanotube interconnects due to contact resistance variations

2008 International Conference on Microelectronics ◽

10.1109/icm.2008.5393530 ◽

2008 ◽

Author(s):

Nisha Kuruvilla ◽

J. P. Raina

Keyword(s):

Carbon Nanotube ◽

Contact Resistance ◽

Latency Analysis

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Horizontal carbon nanotube interconnects for advanced integrated circuits.

MRS Proceedings ◽

10.1557/opl.2013.869 ◽

2013 ◽

Vol 1559 ◽

Cited By ~ 2

Author(s):

Jean Dijon ◽

Nicolo Chiodarelli ◽

Adeline Fournier ◽

Hanako Okuno ◽

Raphael Ramos

Keyword(s):

Carbon Nanotube ◽

Integrated Circuits ◽

Contact Resistance ◽

Unit Length ◽

Specific Contact Resistance ◽

Wafer Surface ◽

Integration Scheme ◽

Vlsi Interconnects ◽

Specific Contact ◽

Individual Tube

ABSTRACTHorizontal carbon nanotube (CNT) interconnects are fabricated using a novel integration scheme yielding record wall densities >1013 shell/cm2, i.e. close to the density required for implementation in advanced integrated circuits. The CNTs are grown vertically from individual via structure and subsequently flipped onto the horizontal wafer surface. Various electrode designs are then used to produce different geometries of metal-to-tube contact such as side contact or end contact. CNT lines - 50 to 100 nm wide and up to 20 µm long - are realized and electrically characterized. The sum of the contact resistances from both ends of the lines is close to 500 Ω for 100 nm diameter lines which leads to a specific contact resistance of 1.6 10-8 Ω.cm2 per tube. With the developed technology, post-annealing of the contact does not improve the resistance values. Both chromium and palladium are used as contact metal. While contact resistance is equivalent with the two metals, the resistance per unit length of the lines does change and is better with palladium. This dependence is explained using a tunnelling model which shows that statistics of individual tube-metal contact is required to properly model the electrical results. Direct experimental evidences showing that only a part of the CNTs in the bundle is electrically connected are also given. Our best line resistivity achieved is 1.6mΩ.cm which is among the best results published for horizontally aligned CNTs and the only one with a realistic geometry for future VLSI interconnects.

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Characterization of Contact and Bulk Piezoresistive Properties of Carbon Nanotube/Styrene-Butadiene-Styrene Composite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.483.537 ◽

2011 ◽

Vol 483 ◽

pp. 537-541 ◽

Cited By ~ 1

Author(s):

Zhi Feng Wang ◽

Ji Min Yang ◽

Xiong Ying Ye ◽

Li Tao Liu ◽

Xu Ming Xie

Keyword(s):

Carbon Nanotube ◽

Contact Resistance ◽

Smart Materials ◽

Composite Films ◽

Resistance Change ◽

Multi Walled Carbon Nanotube ◽

Styrene Butadiene Styrene ◽

Styrene Butadiene ◽

Butadiene Styrene

Carbon nanotube (CNT) filled polymer nanocomposites are increasingly regarded as a realistic alternative to conventional smart materials. In this paper, we studied the contact and bulk piezoresistive properties of multi-walled carbon nanotube/styrene butadiene styrene (MWNT/SBS) composite. Measurements of resistance change under pressure utilizing an Au plate PCB electrode and a sputtered Au layer electrode for same samples were implemented to examine bulk piezoresistivity of the composites and the influence of contact resistance. The results showed that the contact resistance responses to stress for separated electrodes are more remarkable than bulk resistance responses in the MWNT/SBS composite films, but not so stable.

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