>has anyone experience on forming ohmic contacts on highly doped silicon
 >with metals other than aluminum?


Titanium, Tungsten, Tungsten-Titanium and their nitrides and silicides,
Platinum, Cobalt, Nickel

all are relatively common in the semiconductor industry.
best regards,
klaus
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Klaus Beschorner
Metron Technology Europe, PVD (Eclipse) Process Manager
Drosselweg 6,71120 Grafenau,Germany. Tel +49-7033-45683