Short Communication: Stable DRIE-patterned SiO2/Si3N4 electrets for electret-based vibration energy harvesters

TL;DR

This paper introduces a novel DRIE-based manufacturing process for stable SiO2/Si3N4 electrets, enabling durable, high-charge-density electrets suitable for vibration energy harvesters under harsh conditions.

Contribution

It presents a new DRIE-patterned SiO2/Si3N4 electret fabrication method that maintains stability and high surface charge density under demanding environments.

Findings

Electrets achieve up to 5mC/m² surface charge density.

Stable operation at temperatures up to 250°C.

Effective patterning down to 25μm.

Abstract

This paper is about a new manufacturing process aimed at developing stable SiO2/Si3N4 patterned electrets using a Deep Reactive Ion Etching (DRIE) step for an application in electret Vibration Energy Harvesters (VEH). Electrets charged by a positive corona discharge show excellent stability with high surface charge density that can reach 5mC/m^{2} on 1.1\mum-thick layers, even with fine patterning (down to 25\mum) and harsh temperature conditions (up to 250{\deg}C), paving the way to new electret VEH designs and manufacturing processes.