Temperature Dependence of I-V Characteristics for CNT Based p-i-n TFET and n-i-n MOSFET

Abstract

For a carbon nanotube field effect transistor (CNTFET) the ballistic I-V characteristics have been investigated theoretically with respect to ambient temperature for both the p-i-n tunnel FET (TFET) and n-i-n metal-oxide-semiconductor FET (MOSFET). The performance stability of a TFET at higher temperatures, especially in subthreshold regime in which the n-i-n device exhibits a devastating characteristic, is appreciable. Alongside very low subthreshold swing even at a temperature beyond 300 K, a p-i-n tunnel FET could be a more reliable choice for operating in a wide range of temperatures. The subthreshold swing, transconductance, output conductance, saturation mechanism and on/off current ratio are also considered with respect to CNT diameter as well. A lower diameter lessens some negative effects of operating at a high temperature. All the results can be realized based on the energy band diagram of the device and the Fermi functions of source and drain. This trend gives a valuable insight into exploring the changes in 1D device characteristics.