Analog to n-doped semiconductors, the holes are the majority charge carriers, free electrons are the minority charge carriers. Due to positive holes these semiconductors are called p-conductive or p-doped. They have three to six valence electrons, so they can lose or gain electrons. They have three to six valence electrons, so they cannot lose electrons easily. Again, the dopant is fixed in the crystal lattice, only the positive charges can move. They have one or two valence electrons, so they can lose or gain electrons. With the inclusion of an electron, the dopant is negatively charged, such dopants are called acceptors (acceptare, lat. China produces 88 of the world’s antimony. Antimony can also be found as the native metal. It is extracted by roasting the antimony(III) sulfide to the oxide, and then reducing with carbon. It is most often found as antimony(III) sulfide. The necessary energy to lift an electron into the energy level of indium as a dopant, is only 1 % of the energy which is needed to raise a valence electron of silicon into the conduction band. Antimony is not an abundant element but is found in small quantities in over 100 mineral species. The holes move in the opposite direction to the movement of the electrons. Boron, which only has three valence electrons, behaves much like a metal during chemical reactions by. Therefore the electrons in the valence band become mobile. This is the driver of their reactivity/chemical behavior. The 3-valent dopants can catch an additional outer electron, thus leaving a hole in the valence band of silicon atoms. In contrast to the free electron due to doping with phosphorus, the 3-valent dopant effect is exactly the opposite.
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