Marching Velocity of Capillary Meniscuses in Microchannels
Caltech Micromachining Laboratory
Project Abstract
This paper describes a new method and an analytical model for characterizing the
surface energy inside a microchannel using the measurement of the marching velocity of
a capillary meniscus. This method is based on the fact that surface tension of a liquid
meniscus in a hydrophilic case produces pressure to pull liquid into the channel and the
velocity of the meniscus is related to the surface energy. Both Parylene and silicon
nitride microchannels with different surface conditions were fabricated to perform the
liquid-filling experiments. It is shown that our model agrees well with the data and this
is a valid method.
Involved Personnel
Lung-Jieh Yang*, Tze-Jung Yao, Yu-Lin Huang*, Yong Xu and Yu-Chong Tai