METHOD OF FORMING ULTRA SHALLOW JUNCTIONS

THE PRESENT INVENTION RELATES TO A METHOD OF FABRICATING A SEMICONDUCTOR DEVICE (FIGURE 1). IN SPECIFIC EMBODIMENTS, THE METHOD COMPRISES PROVIDING A SEMICONDUCTOR SUBSTRATE, AND ION IMPLANTING DOPANT IMPURITIES OVER A TIME PERIOD INTO THE SEMICONDUCTOR DEVICE BY VARYING AN ION ENERGY (102) OF IMPLANTING THE DOPANT IMPURITIES (20) OVER THE TIME PERIOD.THE DOPANT IMPURITIES (20) ARE ACTIVATION ANNEALED TO FORM ONE OR MORE DOPED REGIONS (22) EXTENDING BELOW THE SURFACE OF THE SEMICONDUCTOR SUBSTRATE.THE ION ENERGY MAY BE VARIED CONTINUOUSLY OR IN A STEPWISE MANNER OVER THE TIME PERIOD (FIGURE 5), AND MAY ALSO BE VARIED IN A CYCLICAL MANNER (FIGURE 4).(FIG 2)