A suspended CNTFET device.
Yet another CNTFET device geometry entails suspending the nanotube more than a trench to reduce contact with the substrate and gate oxide. This technique has the benefit of reduced scattering at the CNT-substrate interface, enhancing device overall performance. There are numerous methods used to fabricate suspended CNTFETs, ranging from growing them over trenches using catalyst particles, transferring them onto a substrate and then under-etching the dielectric beneath, and transfer-printing onto a trenched substrate.
The main problem suffered by suspended CNTFETs is that they have very limited material options for use because a gate dielectric (generally air or vacuum), and applying a gate bias has…show more content… There have been several works done on passivating the nanotubes with different polymers and increasing their lifetime.
Carbon nanotubes are less reliable when they are operated under high electricfiled and high temperature.In metallic gate CNT Avlanche breakdown occurs rapidly . Unlike avalanche behavior in silicon, avalanche in CNTs is temperature Independent. at high voltages heighr than the avalanche point causes Joule heating and breakdown finally in CNTs. This issue has been analysed, and is is observed that the multi-channeled structure can enhance the reliability of the CNTFET. The multi-channeled CNTFETs can works for months for several months period, while the single channeled CNTFETs are usually out of work after a few weeks in the ambient atmosphere. The multi-channeled CNTFETs keep operating when some channels break down because they have multiple channels but in case of single-channeled ones they only have one channel whose breaking down will bring the sysytem