Mo-PHS-01 - Improving Cavity Pressure Stability as Enabler for High-Performance 2-Cavity MEMS Chips

Event

EUROSENSORS 2026
2026-09-06 - 2026-09-09
Zurich

Band

Poster

Chapter

Physical Sensors

Author(s)

A. Breitling - Robert Bosch GmbH,Reutlingen (Germany)

Pages

543 - 544

DOI

10.5162/eurosensors2026/Mo-PHS-01

ISBN

978-3-910600-12-6

Price

free

Abstract

The integration of multiple sensors, such as gyroscopes and accelerometers for Inertial Measurement Units (IMUs), onto a single MEMS chip requires separate, stable cavity pressures. This paper presents a systematic analysis to quantify mechanisms which lead to changes in cavity pressure using a dedicated test vehicle. We demonstrate that gas diffusion through buried oxide layers is the dominant cause of pressure drift. Based on this finding, we developed and validated a gas diffusion barrier that reduces pressure drift by 97%, enabling the fabrication of high-performance, long-life 2-cavity MEMS chips.