Mesoscopic transport phenomena in ultrashort channel MOSFETs

Mesoscopic transport phenomena in the low temperature behavior of MOSFETs with channel lengths down to 30 nm are demonstrated. N-channel MOSFETs show reproducible unexpected periodic transconductance oscillations in the drain current ID versus gate voltage VG characteristics. The oscillations, present from the sub-threshold region up to strong inversion, are reproducible from sample to sample and with temperature cycling. No dependency of the oscillation period on gate oxide thickness or channel length could be observed and the period of the oscillations does not change in magnetic ®elds up to 15 T. Various electric transport models for MOS systems are analyzed, such as hopping conduction, resonant tunneling, universal conductance ̄uctuations, weak interference between source and drain junctions, carrier density quantization and Coulomb blockade. # 1999 Elsevier Science Ltd. All rights reserved.