Qui,
I have used silver epoxy to bond GaAs chips in the past with varying
success.  It works fairly well in a low duty cycle device that remains
cool.  Since you are bonding to diamond, I assume that you are trying
to remove heat from the device.  Unfortunately, silver epoxy has very
poor thermal characteristics and you will therefore not derive the
benefits of bonding to diamond.  A better way would be to use indium
(soft solder) or Au-Sn solder (more brittle).  If you have other
specific questions, feel free to contact me directly.

Brad Cantos
brad.cantos@holage.com
http://holage.com

LinkedIn: http://www.linkedin.com/in/bradcantos

On Mar 13, 2009, at 9:14 AM, QiuWeibin wrote:

> Hi All,
>
>    I hope to bond GaAs wafer onto diamond substrate with silver
> paste? is there anyone who has experiences on it? or is there any
> suggestion? thanks a lot
>
> Qiu