Conductance distribution in nanometer-sized semiconductor devices due to dopant statistics

TL;DR

This paper investigates how individual dopant atoms influence the electrical conductance in nanometer-sized semiconductor devices, revealing increased variability and resonant tunneling effects at small scales due to dopant distribution.

Contribution

It provides a statistical analysis linking dopant atom distribution to conductance variability in devices as small as 15 nm, highlighting the dominant role of dopants.

Findings

Conductance variability increases as device size decreases.

Resonant tunneling features are observed at low temperatures.

Dopant distribution explains conductance fluctuations statistically.

Abstract

We show that individual dopant atoms dominate the transport characteristics of nanometer sized devices, by investigating metal semiconductor diodes down to 15 nm diameter. Room temperature measurements reveal a strongly increasing scatter in the device-to-device conductance towards smaller device sizes. The low-temperature measurements exhibit pronounced features, caused by resonant tunneling through electronic states of individual dopant atoms. We demonstrate by a statistical analysis that this behavior can be explained by the presence of randomly distributed individual dopant atoms in the space charge region.