Electro-Optical Properties of Solar Cell Emitters Fabricated by Plasma Immersion Ion Implantation and Flash Lamp Millisecond Annealing

Both mono- and multicrystalline p-type silicon wafers were used for the phosphorous ion implantation. After ion implantation the silicon is strongly disordered or amorphous within the ion range. Therefore subsequent annealing is required to remove the implantation damage and to activate the doping element. During FLA, only the wafer surface is heated homogeneously to very high temperatures at ms time scales, resulting in the annealing of the implantation damage and an electrical activation of the phosphorous. It is demonstrated that FLA at 800 oC for 20 ms even without preheating is sufficient to recrystallized implanted silicon. The highest recrystallization and the lowest resistivity were obtained after annealing at 1200 oC for 20 ms both for mono- and multicrystalline silicon wafers. Photoluminescence results point towards P - cluster formation at high annealing temperatures which effects on metal impurity gettering within the emitter.