Transport properties of single-walled carbon nanotube transistors after gamma radiation treatment

Single-walled carbon nanotube field-effect transistors (CNT-FETs) were characterized before and after gamma radiation treatment using noise spectroscopy. The results obtained demonstrate that in long channel CNT-FETs with a length of $10\mu \text{m}$ the contribution of contact regions can be neglected. Moreover, radiation treatment with doses of $1\times {10}^6$ and $2\times {10}^6\text{rad}$ allows a considerable decrease parallel to the nanotube parasitic conductivity and even the shift region with maximal conductivity to the voltage range of nearly zero gate voltage that improves the working point of the FETs. The Hooge parameters obtained before and after gamma radiation treatment with a dose of $1\times {10}^6\text{rad}$ are found to be about $5\times {10}^{-3}$ . The parameters are comparable with typical values for conventional semiconductors.