Subject: Why is silicon used in computers instead of copper

If price or availability was the reason, I would think copper is cheaper and 
more available.
If ease/cost of working with it is the issue, copper has a lower melting 
point.
As for the most obvious factor, copper conducts electricity better than 
silicon.
Could it be that since silicon doesn't conduct as well, it has more time to 
process information?

Re: Why is silicon used in computers instead of copper