Effect of rare earth oxide CeO2 on the anodic bonding performance of PEG-based MEMS encapsulation materials

Chao Du,Xu Yin,Haocheng Zhao,Cuirong Liu

doi:10.1177/16878140211007712

Abstract

Herein, we synthesized a new polyethylene glycol (PEG)-based solid polymer electrolyte containing a rare earth oxide, CeO2, using mechanical metallurgy to prepare an encapsulation bonding material for MEMS. The effects of CeO2 content (0–15 wt.%) on the anodic bonding properties of the composites were investigated. Samples were analyzed and characterized by alternating current impedance spectroscopy, X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, tensile strength tests, and anodic bonding experiments. CeO2 reduced the crystallinity of the material, promoted ion migration, increased the conductivity, increased the peak current of the bonding process, and increased the tensile strength. The maximum bonding efficiency and optimal bonding layer were obtained at 8 wt% CeO2. This study expands the applications of solid polymer electrolytes as encapsulation bonding materials.

Highlights

Encapsulation is an important part of the production process of microelectromechanical systems (MEMS) because it affects the service life of MEMS
We found that polyethylene oxide (PEO) complexed with lithium perchlorate can be anodically bonded to metal, while the polyethylene glycol (PEG) and PEO have similar anodic bonding properties and are better than PEO
The surface characteristics of the material are an important part of its anodic bonding performance

Summary

Introduction

Encapsulation is an important part of the production process of microelectromechanical systems (MEMS) because it affects the service life of MEMS. When the content of CeO2 was 8 wt.%, the surface characteristics of the solid electrolyte changed obviously, the disordered crystal structure became ordered, and the size of the crystal decreased obviously, such a feature is more conducive to the movement of ions within the crystal.

Results

Conclusion