Share Email Print

Proceedings Paper

Thermal flow sensor with vacuum-sealed membrane fabricated by surface micromachining
Author(s): Chi-Hoon Jun; Suk Koon Kim; Dong-Seong Kwag; Youn Tae Kim
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We have proposed a surface-micromachined microflow sensor to solve the problems of poor thermal isolation and low sensitivity presented in typical thermal flow sensors. The membrane of insulating films on a vacuum cavity formed in a silicon substrate supports a n+) poly-Si heating resistor and two bidoped poly-Si thermopiles. We have investigated heat-transfer characteristics of the sensor microstructure with the 5-micrometers -depth cavity of 100 X 100 micrometers 2 and nitrogen and water as the working fluid using a 2D numerical analysis in terms of the hater power, inlet flow velocity and pressure inside the cavity. The microstructure with the vacuum cavity shows improved thermal isolation compared to the air cavity, suppressing heat loss from the heater to the substrate. With the vacuum cavity heaving an optimized geometry, it is possible to enhance the performance of the thermal microflow sensor.

Paper Details

Date Published: 10 March 1999
PDF: 8 pages
Proc. SPIE 3680, Design, Test, and Microfabrication of MEMS and MOEMS, (10 March 1999); doi: 10.1117/12.341160
Show Author Affiliations
Chi-Hoon Jun, Electronics and Telecommunications Research Institute (South Korea)
Suk Koon Kim, Kyungpook National Univ. (South Korea)
Dong-Seong Kwag, Hanyang Univ. (South Korea)
Youn Tae Kim, Electronics and Telecommunications Research Institute (South Korea)

Published in SPIE Proceedings Vol. 3680:
Design, Test, and Microfabrication of MEMS and MOEMS
Bernard Courtois; Wolfgang Ehrfeld; Selden B. Crary; Wolfgang Ehrfeld; Hiroyuki Fujita; Jean Michel Karam; Karen W. Markus, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?