Dear Bob,

Hello, you may be able to fill this with a glass frit powder applied with a
doctor blade? or you can use a spin on polymer that may fill this
trench.  Some of these frits are used for glass passivation of medium power
solid state devices and the moats they fill are quite large. The powders
are ground to a size near 25 microns and they soften and melt at or below
the temperatures you mention.

Of course the polymer is not an SOG but can permanently or temporarily fill
the trench and then could be heated and removed leaving an air gap or
bridge if this is of interest?

There are some types of SOG that can do 1 micron but filling this trench I
think would be difficult. There is one type of SOG that does flow at a temp
of 180 deg c perhaps this might be of interest I would think a slow spin
for dispersion and gap fill may have some potential but this is something
that would require some empirical work.

I have mixed the Frit with the SOG and can get a fairly uniform
distribution of glass particles when spun. The glass frit can also be silk
screened on or applied using electrophoresis.

If you have interest let me know I can provide some names.

Hope this can help you.

Neal
Neal@zbzoom.net


t 01:22 PM 5/16/2005 -0700, you wrote:
>Has anyone ever tried dielectric material to fill deep trenches of 1
>micron by 20 microns deep. Unfortunately, we need to be able to process
>silicon at temperatures > 1100 Degrees C. Is there any SOG that would fit
>this application. Most everything I have researched is limited to around
>500 degrees. Thanks in advanced. Bob Henderson