Share Email Print

Proceedings Paper

Solder-bonded micromachined capacitive pressure sensors
Author(s): Berthold Rogge; David Moser; Hermann H. Oppermann; Oliver Paul; Henry Baltes
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We report the first solder-bonding of low-cost silicon absolute pressure sensors. The goal of the work is to solder a pressure sensor wafer and a CMOS wafer containing the signal conditioning circuitry together face to face under vacuum. The result is a very flat capacitive absolute pressure sensor which can be used in harsh environments for automotive, medical, barometric, and other applications. We successfully demonstrated this approach using sensor wafers with micromachined silicon membranes and CMOS wafers without signal conditioning circuitry. Solder frames surrounding the membrane are electroplated on the sensor wafer. Different solder materials such as Au/Sn and SnPb were examined. Characterization of the hermetic prototypes in a pressure chamber showed a sensitivity of 0.8 fF/mbar, in good agreement with finite (FE) element simulations. With special regard to the sensitivity of the sensor a quadratic membrane, a rectangular membrane and a square membrane with a boss, all with an area of 2.25 mm2, were compared using FE analysis. The rectangular membrane has the largest sensitivity.

Paper Details

Date Published: 8 September 1998
PDF: 9 pages
Proc. SPIE 3514, Micromachined Devices and Components IV, (8 September 1998); doi: 10.1117/12.323902
Show Author Affiliations
Berthold Rogge, Swiss Federal Institute of Technology (Switzerland)
David Moser, Micronas Semiconductor SA (Switzerland)
Hermann H. Oppermann, FhG/IZM (Germany)
Oliver Paul, Swiss Federal Institute of Technology (Switzerland)
Henry Baltes, Swiss Federal Institute of Technology (Switzerland)

Published in SPIE Proceedings Vol. 3514:
Micromachined Devices and Components IV
Patrick J. French; Kevin H. Chau, Editor(s)

© SPIE. Terms of Use
Back to Top