Rhodium/Aluminum interaction in testing ICs

I am in semiconductor industry. We are trying to electrical test ICs. ICs have Aluminum pads. Probes used to test the die are made of Rhodium. We are seeing black contamination build up on these probes. The current pumped through during the test is high. So, I am thinking there is some galvanic activity going on. The black build up prevents us from further testing. Anyone know what may be happening?

Haven't got the foggiest. However Tungsten probes are a possibility. You can make them from Tungsten wire and an Oxy-Hydrogen torch. After lots of practice you can get an unbelievably fine point by starting about two inches from the end and drawing the wire through the flame at a decreasing rate. Adjust the torch flame to be Oxygen-rich. Wear welding goggles, it's bright!