Where the
world gathers for metal finishing
Q&As since 1989


-----

Nickel-Contaminated Silicon-Wafer

We need some metal contaminated Wafer of silicon for equipment calibration purpose. The equipment is a so-called TREX and detects Contamination (e.g. Elements) near the surface around 2nm deep. It's detection limit is around 10 to 10 atoms per square centimeter which may be around 0,01% contamination.

We want to perform measurement on a regular basis to confirm the stability of the measurement equipment. Because nickel may be one of the long term constant contaminations in silicon we prefer nickel. The concentration should be around 10 to 10, 10 to 11, 10 to 12 and 10 to 13 so in total we ask for a set of four wafers. Do you know a supplier?

Dr. Magnus Kolter
- Alsdorf, Germany
2000

---

Dr. Kolter

Regarding the process you described, we specialize in the Chemical Vapour Deposition of nickel and this can provide you with a solution.

Our process will be able to deposit a few microns (or up to a few centimeters, if necessary) of ultra-pure nickel onto the silicon.

If you can supply the dimensions of the pieces to be deposited on, we will provide a quote. Sincerely,

Mick O'Meara
- Toronto, Canada
2000

---

Let me get this straight. You need to detect trace levels of contamination, about 10E10 to 10E13 atoms per sq. cm., on pure semiconductor grade silicon wafer. This is to calibrate the equipment. Since there are of the order of 10E21 atoms/sq.cm. on a solid surface, this 0.01% does not sound right. Anyway! You need Ion Implantation of nickel on Si. These levels are of the order used in implanting gates (through gate oxide)in MOS circuits within 5% accuracy (is that what is your final application?).

The only metal ion implantation company I know is ISM Technology near San Diego, CA. Jim Treglio is a frequent visitor to this web-site. Check with him. I get the feeling that this procedure will need a little development time to get to the right numbers.

Mandar Sunthankar
- Fort Collins, Colorado
2000