Energy-band engineering for improved charge retention in fully self-aligned double floating-gate single-electron memories

TL;DR

This paper introduces a novel self-aligned single-electron memory with Si and Ge floating gates, leveraging energy band engineering to enhance charge retention and enable room-temperature operation.

Contribution

It presents a new design of a fully self-aligned single-electron memory utilizing different material floating gates to improve charge retention through energy band engineering.

Findings

Devices show long retention times.

Single-electron injection achieved at room temperature.

Energy barriers are enhanced by conduction-band offset.

Abstract

We present a new fully self-aligned single-electron memory with a single pair of nano floating gates, made of different materials (Si and Ge). The energy barrier that prevents stored charge leakage is induced not only by quantum effects but also by the conduction-band offset that arises between Ge and Si. The dimension and position of each floating gate are well defined and controlled. The devices exhibit a long retention time and single-electron injection at room temperature.