Steps on current-voltage characteristics of a silicon quantum dot covered by natural oxide

TL;DR

This paper derives conditions for step-like current-voltage characteristics in silicon quantum dots with natural oxide, linking doping atom count to current steps, and confirms feasibility in experimental structures.

Contribution

It introduces simple conditions for step-like I-V curves in silicon quantum dots influenced by doping atoms, providing a practical framework for experimental realization.

Findings

Current steps are proportional to the number of doping atoms.

Conditions for step-like behavior are feasible in existing structures.

Current step height is approximately 1.2 pA times the number of dopants.

Abstract

Considering a double-barrier structure formed by a silicon quantum dot covered by natural oxide with two metallic terminals, we derive simple conditions for a step-like voltage-current curve. Due to standard chemical properties, doping phosphorus atoms located in a certain domain of the dot form geometrically parallel current channels. The height of the current step typically equals to (1.2 pA)N, where N=0,1,2,3... is the number of doping atoms inside the domain, and only negligibly depends on the actual position of the dopants. The found conditions are feasible in experimentally available structures.