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Adhesion layer between Si and Au

Hi, my name is Charles Garson and currently working with Bio-MEMS. I am looking at different adhesion layers for electroplating Au to Silicon. Right now I'm trying an evaporated Cr 300A - Cu 3000A - Au 300A adhesion layer, is there a better choice for adhesion to silicon? I am trying to get away from a three layer deposition of metal.

Charles Joesph Garson
Center for Applied Science and Engineering - Springfield, Missouri
2005

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Hello!

I am interested in the same field of work. I work as a Ph.D. student at the Angstrom laboratory.

So far I've heard that chromium and titanium is the metals that are mostr common to use as adhesion layers to gold.

My substrate is 650nm is SiO2 and on top of that I have ~100 angstroms of Cr with ~100-200nm of Au on top. The gold seems to adhere quite well so far...

Best regards
Tobias, Uppsala/Sweden

Tobias Blom
Uppsala University - Uppsala, Sweden
2005

Cr-Au and Ti-Au are regularly used on SiO2 crystals where high temperature will not be an issue. Ti-Pt-Au is the preferred high temperature solution. Group V refractories may balance adhesion and barrier metal properties.

Jeff Andle
- Westbrook, Maine
2005

A so called barrier layer is preferred between the bottom adhesion layer and a top solderable/bonding layer such as gold where long term reliability needs to be assured. The barrier prevents diffusion of top and bottom layers into each other. The typical barriers are Ni, Pd, and Pt. There could be others.

Mandar Sunthankar
- Fort Collins, Colorado
2005

I am a student and I am looking at Cr/Au as the top electrode for my capacitor. I will be doing reliablity test later on, which is to heat up the capacitor at 150 °C for a minimum of one week. So, my question is, will Cr/Cu be stable at this temperature? if not, what metal stack should I be looking at?

Susan Jacob
- Fayetteville, AR, USA
January 13, 2009