Carbon nanotubes set for electronic applications

The finding is good news for all commercial applications of carbon nanotubes, which are currently held back by substantially higher costs relative to existing materials.

The real advantage, however, lies in the production of micro electronics, where temperature is critical in the manufacturing process, as Dr Vlad Stolojan of Surrey University’s Advanced Technology Institute explained.

’When you make a semiconductor chip, such as the microprocessor in your laptop, you usually end up with several layers of different materials, including silicon, doped silicon, oxide, metal contact [and so on]. The main issue with high temperature is that all these layers will expand/contract at slightly different rates, leading to high strains such as cracking, delamination… so manufacturers have to constrain the temperature that this device reaches to below 400^oC.’

The research team, which is headed by Prof Ravi Silva, showed in 2002 that nanotubes can be grown while keeping the silicon below 500^oC. However, the nanotubes were defective and not any better electrical and thermal conductors than copper.