ANALYSIS OF ION-IMPLANTED SILICON USING HIGH-RESOLUTION X-RAY-DIFFRACTION

High-resolution X-ray diffractometry was used to measure the strain du e to implantation of Ge ions into silicon wafers. (001)- and (111)-ori ented Si wafers were implanted with 320 keV and 640 keV Ge ions at dif ferent doses. Simulations based on the dynamical theory of diffraction were compared with measured X-ray rocking curves. A description of ho w strain is taken into account in the simulations is given. We find th at the strain in the Si wafers can be described by a linear combinatio n of strain proportional to the implanted ion distribution and of stra in proportional to the radiation damage distribution. At low doses (al most-equal-to 10(13) CM-2) the strain profile is dominated by the dama ge profile, at high doses (greater than or similar to 10(14) CM-2) the strain profile follows the ion distribution. The maximum strain incre ases roughly linear with dose until amorphization occurs. Rapid therma l annealing experiments reveal that the damage-related strain disappea rs at temperatures of 700-800-degrees-C. Further annealing at temperat ures up to 1050-degrees-C is necessary to remove also the ion-related strain.