Tunneling field effect transistor having buried drain structure

Abstract

A tunneling field effect transistor having a buried drain structure is provided. The tunneling field effect transistor comprises a semiconductor pattern disposed on a substrate and including a thin part at one end, a thick part at the other end, and a step between the thin part and the thick part. A drain electrode is disposed on the thin part, a source electrode is disposed on the thick part, and a gate electrode is disposed on the thick part between the drain electrode and the source electrode. A gate insulating layer is disposed between the semiconductor pattern and the gate electrode and between a sidewall of the step of the semiconductor pattern and the drain electrode. The semiconductor pattern has a drain region of a first conductivity type induced by generation of a charge plasma of the first conductivity type in an area adjacent to the drain electrode, and a source region of a second conductivity type induced by generation of a charge plasma of the second conductivity type in an area adjacent to the source electrode, and a channel region between the source region and the drain region. A thickness of the drain electrode is lower than a height of the step of the semiconductor pattern.