I suppose it might depend on the structures involved in the bonding.
When we were making pressure transducers with a pyrex substrate (pyrex
to silicon bonding) there was no pressure required.  The electrostatic
attraction created plenty of pressure to hold the parts together.

Chang-Hwan Choi wrote:

> Hi.
>
> First, I want to ask about the contacting pressure in
> the anodic bonding. I have read some paper saying that
> mechanical pressure would not be so important in
> anodic bonding. But, other paper say that high
> pressure to press wafers would be important.
> Dose pressure matter much in anodic bonding? If then,
> how much pressure is needed?
>
> Secondly, I tried bonding Pyrex with a-Si layer which
> was from PECVD. But, I could not get a bonding. I know
> that some people bonded Pyrex with a-Si or Poly-Si
> layer which was from LPCVD. But, I would like to use
> PECVD deposited a-Si layer. Is there someone who has a
> experience of anodic bonding between pyrex to a-Si
> layer from PECVD? Is it possible to get a bond between
> pyrex to a-Si layer from PECVD anyway?
>
> Thanks.
>
> Best Regards,
> Chang
>
> =====
> Chang-Hwan Choi
> Brown University
> Division of Engineering, Box D
> 182 Hope Street, Providence, RI 02912, U.S.A.
> Tel: (401)351-3915(H), (401)863-3011(O)   Fax: (401)863-9028
> Email: [email protected]
> URL: http://myhome.naver.com/4chchoi
>
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