Hi, I was just doing some reading on semiconductors mostly with respect to photovoltaic cells. I understand that doping silicon with Boron and Phosphorus creates a good semiconductor because the extra electrons from the phosphorus jump over to the 'holes' provided by boron, and then creating holes on the phosphorus side. But why not dope the silicon with a 2 valence element and a 6 valence element so you would double the amount of electrons jumping over? I suspect that this is because it would take more energy to get the electrons to jump, but it doesn't make sense in my head. I just basically would like to discuss how this works as it is a new concept to me and I think I could learn a lot just by talking about it.