Disclosed is a CNT technology that overcomes the intrinsic ambipolar properties of CNTFETs. One embodiment of the invention provides either a stable p-type CNTFET or a stable n-type CNTFET. Another embodiment of the invention provides a complementary CNT device. In order to overcome the ambipolar properties of a CNTFET, source/drain gates are introduced below the CNT opposite the source/drain electrodes. These source/drain gates are used to apply either a positive or negative voltage to the ends of the CNT so as to configure the corresponding FET as either an n-type or p-type CNTFET, respectively. Two adjacent CNTFETs, configured such that one is an n-type CNTFET and the other is a p-type CNTFET, can be incorporated into a complementary CNT device. In order to independently adjust threshold voltage of an individual CNTFET, a back gate can also be introduced below the CNT and, particularly, below the channel region of the CNT opposite the front gate. In this manner parasitic capacitances and resistances are minimized.