[mems-talk] Electrical contact on organic samples

[jpt sharma]

Hi Kirt
  The problem is the  size of the samples are of the order of microns. about 20-50 microns.
  Thanks
  

Kirt Williams <kirt_williams at sbcglobal.net> wrote:
  Since you're making a four-probe measurent, the dimensions of the metal 
contacts are probably on the order of a millimeter.
This is large enough for shadow masking:
1. Make a mask from a thin sheet of material with holes where you want the 
pad.
2. Firmly clip the mask to the organic substrate. It is critical that there 
not be a gap between the shadow mask and the substrate. And you don't want 
it to shift during deposition.
3. Evaporate or sputter metal.
4. Remove mask and you're done.

The hardest part is making the shadow mask. You may get useful results with 
pinholes in piece of foil or drilled holes in sheet metal.
For more-complex shapes, I've used DRIE to make patterns in a silicon wafer.

--Kirt Williams