PNNL-13501 - Pacific Northwest National Laboratory

Plastic Laminate Bonding Processes Development
Methods were developed for bonding laminated plastic
microchannel structures similar to those produced
routinely using patterned metal shims. The laminated
metal devices were formed using a high-temperature
diffusion bonding process to fuse the assembled shims
into a solid metal structure. Bonding of plastic shims
must be accomplished at relatively low temperatures to
1) avoid thermal degradation or melting of the plastic
material, and 2) avoid distortion of the completed device
resulting from the high thermal expansion coefficients of
many plastics (up to 10 times greater than the coefficients
of typical metals). We developed a method for applying
adhesives to patterned plastic shims. This method
allowed the coated shims to be assembled into a stacked
device, then the resin was thermally activated in a hot
press to bond the assembly. An example of a series of
microchannels produced in a plastic device using this
method is shown in Figure 1. A procedure was also
developed for bonding polycarbonate cover plates directly
to polycarbonate chips containing laser machined
microfluidic flow features without distorting the
machined features and without the need for an adhesive
layer. This allows the production of microchannels
having uniform chemical properties on all surfaces of the
enclosed channel.
Figure 1. Cross section of microchannels in a bulk
polyimide part produced by laminating 125 micron-thick
laser-patterned polyimide shims. The channels are 125 µm
high, 2.5 and 1.0 mm wide, and 28 mm long before being
cross sectioned.
Design and Fabrication of Electro-Gas-Dynamic Fan
A meso-scale plastic-based device was designed that will
allow slight pressurization of a gas feed (Figure 2). The
device, using electro-hydrodynamic principles to produce
and accelerate ionized gas species, moves nonionized gas
by molecular collisions. The circular design of the device
promotes an acceleration and pressurization of the gas,
which is introduced at the center, as it moves toward the
outer rim. We anticipate that such a device may have
applications for space missions where low pressure
background gases need to be collected and pressurized for
chemical processing.
Figure 2. Meso-scale plastic electro-hydrodynamic fan
Summary and Conclusions
This project enhanced Pacific Northwest National
Laboratory’s in-house microfabrication capabilities by
• allowing development of laser micromachining
expertise on the Resonetics Maestro micromachining
station
• developing bonding technologies for laminated
plastic devices
• developing a meso-scale electro-hydrodynamic fan.
Publications and Presentations
Martin PM, DW Matson, WD Bennett, and JW Johnston.
2000. “Thin film optical materials for use in microtechnology
applications.” Presented at the Society of
Vacuum Coaters 43 rd Annual Technical Conference, April
17-21, Denver. In Proceedings of the Society of Vacuum
Coaters 43 rd Annual Technical Conference (submitted).
Martin PM, DW Matson, WD Bennett, DC Stewart, and
CC Bonham. 2000. “Laminated ceramic microfluidic
components for microreactor applications.” In Topical
Conference Proceedings of IMRET 4, and presented at
IMRET 4, 4 th International Conference on Microreaction
Technology, March 5-9, pp 410-415.
Materials Science and Technology 323