It's not just sand. It's sand with the oxygen removed. The oxygen (especially every last atom) doesn't want to leave.
Silicon has to be purified to 99.9999% at the very least to make a crappy solar cell. Add four more 9's to get to making decent microprocessors. Getting certain impurities out (that behave exactly like silicon in a chemical sense) is really difficult.
Silicon has to be purified to 99.9999% at the very least to make a crappy solar cell. Add four more 9's to get to making decent microprocessors. Getting certain impurities out (that behave exactly like silicon in a chemical sense) is really difficult.