New DRIE-Patterned Electrets for Vibration Energy Harvesting

TL;DR

This paper introduces a novel DRIE-based manufacturing process for creating stable, high-charge-density electrets suitable for vibration energy harvesting, demonstrating excellent stability under harsh conditions.

Contribution

It presents a new DRIE-patterned electret fabrication method that enhances stability and charge density for electret-based energy harvesters.

Findings

Electrets show high surface charge density up to 5mC/m^2.

Patterned electrets remain stable at temperatures up to 250°C.

The process enables new designs for vibration energy harvesters.

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-based Vibration Energy Harvesters (e-VEH). This process consists in forming continuous layers of SiO2/Si3N4 electrets in order to limit surface conduction phenomena and is a new way to see the problem of electret patterning. Experimental results prove that patterned electrets charged by a positive corona discharge show excellent stability with high surface charge densities that may reach 5mC/m^2 on 1.1\mu m-thick layers, even with fine patterning and harsh temperature conditions (up to 250{\deg}C). This paves the way to new e-VEH designs and manufacturing processes.