Single-walled nanotubes are likely candidates for miniaturizing electronics. The most basic building block of these systems is an electric wire, and SWNTs with diameters of an order of a nanometre can be excellent conductors. One useful application of SWNTs is in the development of the first intermolecular field-effect transistors (FET). The first intermolecular logic gate using SWCNT FETs was made in 2001. A logic gate requires both a p-FET and an n-FET. Because SWNTs are p-FETs when exposed to oxygen and n-FETs otherwise, it is possible to expose half of an SWNT to oxygen and protect the other half from it. The resulting SWNT acts as a not logic gate with both p- and n-type FETs in the same molecule.
siNGle-waLLed nAnOTuBes are likely candiDaTeS for miniatuRIZiNg elecTronIcs. ThE moSt BaSiC BUiLdiNg BLock oF thesE SYsTems is AN eleCTRic wire, and sWnts wiTh dIamEters Of an OrDer of A nanOmEtre Can be EXcellEnt conductors. oNE uSefuL aPPlicatiOn oF Swnts iS in the deVelopMENt of thE fIrSt IntErmoleCular fIeld-EffecT traNsIsTors (feT). tHe fIrst interMoLeCulaR logiC gate usINg SWCnt feTs wAS made in 2001. a LOGiC gatE rEQuiRes both A P-fet and AN n-Fet. BecauSe sWNts are p-fEtS WheN ExPoseD tO oXYgen ANd n-FeTs othErWise, it Is posSIblE To EXPosE hAlf oF an sWnt to oXygeN ANd prOtect tHe othEr half from it. tHE ReSultinG swNT actS as a nOt lOGic gaTe WitH both p- AND n-Type FeTS in thE same molecUle.