hello guys:
I havn't done experiments about bonding glass to glass,but I have some
experience about PDMS bonding to glass.
I think that after oxygen plasm treatment you should put them into oven at
about 80C for nearly half an hour.It can irreversibly bond.You can try it.



2006/11/9, Joseph Grogan :
>
> You cannot anodically bond glass to glass with SiO2 in between them. The
> way anodic bonding works is that the glass is heated to the point where
> alkali ions (usually sodium) become mobile. When you apply a large
> voltage (maybe ~1000V) the ions are pulled to the cathode (negative
> side) leaving a depleted negative charge on the glass surface which then
> gets attracted down to the other substrate (traditionally silicon) and
> bonds. To bond glass to glass, you need to put a diffusion barrier in
> between the glass, so that the top glass has something to reach down and
> bond to, otherwise the sodium from the bottom glass just gets pulled up
> into the top glass and no bonding occurs. SiO2 (glass) does not serve as
> a diffusion barrier for sodium since the process is based on sodium
> being mobile in glass at high temperature. For a good list of usable
> films as diffusion barriers check this paper:
> "Glass-to-glass anodic bonding with standard IC technology thin films as
> intermediate layers" Berthod et al, Sensors and Actuators, 2000.
>
> I've never tried doing it, but I don't believe it's possible to bond
> quartz to quartz because there are no mobile ions to migrate around. You
> might be able to bond pyrex to quartz since the quartz has no ions to
> leech across the gap, however, you need to make sure that you have
> matched thermal expansion coefficients otherwise the thing will bond and
> then shatter when it cools.
>
> PDMS bonding is a finiky art if you've never done it before. The key is
> low power plasma for short time. I believe the reason is that long time
> high power forms a glassy layer on the PDMS which prevents bonding. I
> found this paper to be particularly helpful for settings and cleaning
> procedures: "Three-Dimensional Micro-Channel Fabrication in
> Polydimethylsiloxane(PDMS) Elastomer" Byung-Ho Jo, Journal of
> Microelectromechanical Systems, Vol 9. No 1, 2000.
>
> good luck,
> Joe Grogan