Hello all,

I have a substrate which is SOI. i.e.

300 microns Silicon
1um SiO2
5 um Si (this is the topmost layer)

I'm going to etch the 5um of Si leaving circular microdots of radius ~
50um and period 200 um. I plan on producing a 50 x 50 array of
microdots, however 10 x 10 microdots would also be ok (start small then
go big).

On top of these microdots I want to fabricate either a metal resistor or
vanadium oxide resistor. Now remember there is a 5 micron step between
the edge of the microdot and the SiO2 substrate.

I need to connect my resistor using Al or Au etc. tracks to square bond
pads at the periphery of my device. I do not know how to realise these
tracks since the metal film will break during deposition . I'm guessing
I shall have to use some sort of sacrificial layer that is 5 um thick so
that the surface is co-planar for the deposition of the metal tracks.
Essentially I require something akin to an air bridge process. One
obvious consideration is how long I can make an air bridge type
structure without the film breaking under the stress.

Any advice is much appreciated.

Thanks!

Dr. James Paul Grant
Postdoctoral Research Associate
Microsystems Technology Group
76 Oakfield Avenue Room 3
University of Glasgow
Glasgow
Scotland
G12 8LS

Telephone: +44(0)141 330 3374