In plasma ion doping operations, a wafer is positioned on a susceptor within a reaction chamber and an ion doping source gas is plasmalyzed in an upper part of the reaction chamber above a major surface of the wafer while supplying a control gas into the reaction chamber in a lower part of the reaction chamber opposite the major surface of the wafer to thereby dope ions into the major surface of the wafer. The ion doping source gas may comprise at least one halide gas, and the control gas may comprise at least one depositing gas, such as a silane gas. In further embodiments, a diluent gas, such as an inert gas, may be supplied to the reaction chamber while supplying the ion doping source gas and the control gas. Related plasma ion doping apparatus are described.