OICC Press International Nano Letters 2228-5326 4 3 (September 2014) 2014 08 26 Investigation of the cutoff frequency of double linear halo lightly doped drain and source CNTFET 10.1007/s40089-014-0118-3 EN Mohammad Javad Hejazifar Department of Electrical Engineering, Guilan Science and Research Branch, Islamic Azad University, Guilan, IR Seyed Ali Sedigh Ziabari Department of Electrical Engineering, Roudbar Branch, Islamic Azad University, Roudbar, IR Journal Article 2014 08 26 Abstract In this work we investigate the n-type single halo implantation in channel of lightly doped drain and source CNTFET (SH-LDDS-CNTFET) and propose the n-type double linear halo implantation in the channel of LDDS-CNTFET. These transistors are simulated with a non-equilibrium Green’s function method. We demonstrate that in the proposed structure the f T at the V GS ranges of 0–0.25 V and more than 0.42 V is much higher compared to the LDDS-CNTFET and SH-LDDS-CNTFET and the SH-LDDS-CNTFET, respectively. Finally, simulations demonstrate that the f T of the proposed transistor is more than the LDDS-CNTFET at a wide range of V GS , whereas the f T of SH-LDDS-CNTFET is more than the LDDS-CNTFET for narrow ranges of V GS .