Scientists have tested the ability of nanotubes to retain electrical properties and memory when exposed to high levels of radiation. They hope this exploration will extend the life of future space missions. The work was published in the journal ACS Nano.
The researchers placed carbon nanotubes on a silicon wafer as a semiconducting layer in field-effect transistors. They tested various configurations of transistors with different levels of shielding (protection of conductors or equipment from interference caused by electromagnetic radiation from other conductors or equipment – “Hi-Tech”), consisting of thin layers of hafnium, titanium and platinum oxide around the semiconductor layer.
The team positioned the transistor between the two shields. Scientists have found that nanotubes protect electrical properties from radiation up to 10 Mrad. This far exceeds the level that radiation-hardened silicon-based devices can withstand. By placing the screen under the transistor, the nanotubes were protected up to 2 Mrad. These figures are equal to the level that radiation-resistant silicon-based electronics can withstand.
To make it easier to manufacture radiation-hardened devices, the team created static memory chips (SRAMs) where they placed a shield under the transistor. Research has shown that these chips have the same stability threshold as silicon-based SRAMs.
This work shows that carbon nanotubes could be a promising addition to next-generation electronics. The service life and range of flights into space are severely limited by the reliability of technology. These one-atom-thick tubes are expected to make transistors more energy efficient than conventional silicon.
