Rare earth minerals in solarcell production

 Rare earth elements aren't really used much in PV at all. The market is dominated by silicon cells (~95% of the market). The next big player is Cadmium Telluride (~5% of the market). The rest are pretty insignificant.

The major one is Indium. Indium Tin Oxide is used as a transparent conductive electrode used to coat the top of the cell. Indium production is a potential bottleneck when it comes to expansion of the PV manufacturing industry and currently costs around $700/kg. Less than 1000 tonnes per year is produced. However, it looks like it may well be replaced with carbon in the form of Graphene.