METHOD FOR FORMING SHALLOW JUNCTIONS IN SEMICONDUCTOR WAFERS USING CONTROLLED LOW LEVEL OXYGEN AMBIENTS DURING ANNEALING

摘要

There is provided a method of forming a shallow junction in a semiconductor wafer into which a dopant material is implanted. The dopant material is activated by heat treating the semiconductor wafer for a selected time at a selected temperature in the heat treatment chamber. The oxygen concentration in the heat treatment chamber during activation of the dopant material is controlled at or near a selected level that is typically less than the background level typically present when the heat treatment chamber is filled with the process gas. The oxygen concentration can be controlled at or near a selected level within a range of less than 1000 ppm, and is preferably controlled at or near a selected level within the range of about 30-300 ppm. This method uses injected boron or BF₂Ions, but may also be used in any dopant material.