Question #1d888
1 Answer
Yes. Natural blue diamonds are semiconductors.
Diamond has a structure similar to silicon, the main difference being that silicon has a much smaller energy gap (band gap) between the bonding orbitals (which are completely full) and the anti-bonding orbitals (which are completely empty).
The band gap in pure diamond is so large that diamond is normally considered a good electrical insulator (although it is a good conductor of heat-hence the nickname, ice). However, with the addition of substitutional impurities, diamond can become a semiconductor. Natural blue diamonds have a small concentration of boron atoms, which substitute for carbon atoms in the lattice. Each boron atom has one fewer electron than carbon, and this leaves positively charged "holes" in the valence band. The holes can move freely in the material, thereby creating a p-type semi-conductor.
