[mems-talk] Bubble formation in mircochannels.

[Torsten Wagner]

Vishwa wrote:
> Hi guys,
> I have been facing this problem of bubble formation in my microchannel. The
> dimensions of the channel are 2.5mm across, 5cm long and 60 microns tall.
> The channel has some ridges on the floor and the bubble seem to collect in
> the channel. 

That's a common problem not only for microchannels but also for standard 
tubes. It will help if you construct a debubbler before the 
microchannels. Heat up the liquid which you like to pump across your 
microchannels slightly. This will dissolve gas inside the liquid which 
might prevent bubbles later. You can use one of your microchannels 
covered by a gas-permeable membrane and heat up this  structure by a 
peltier element. Thus, the bonded gas in your liquid can dissolve and 
pass the membrane.

Thats at least a method I'm aware of in some commercial devices.

Greetings
Torsten