Transistor characteristics of 14-nm-gate-length EJ-MOSFET's

We have fabricated electrically variable shallow junction metal-oxide-silic on field-effect transistors (EJ-MOSFET's) to investigate transport characte ristics of ultrafine gate MOSFET's. By using EB direct writing on an ultrah igh-resolution negative resist (calixarene), we could achieved a gate lengt h of only 14 nm, Despite such an ultrafine gate, the device exhibited trans istor operation at room temperature. From studying the devices with the gat e lengths from 14 nm to 98 nm, we found that when the gate length was below 30 nm the subthreshold leakage current increased. The low-temperature meas urements showed that the leakage current was caused by the classical therma l process and that quantum effects do not play an important role in subthre shold characteristics at room temperature.