Subthreshold conduction

Rather it continues showing an exponential behavior with respect to the subthreshold gate voltage.

Subthreshold slope is used as a figure of merit for the switching efficiency of a transistor.

[4][5] For a technology generation with threshold voltage of 0.2 V, subthreshold conduction, along with other leakage modes, can account for 50% of total power consumption.

[6][7] Some devices exploit sub-threshold conduction to process data without fully turning on or off.

Even in standard transistors a small amount of current leaks even when they are technically switched off.