A nuclear reaction analysis study of boron implanted at low energy into silicon

Abstract Single crystals of n-type 〈100〉 silicon have been implanted at room temperature with BCl 2 molecular ions at two different energies of 15 and 30 keV, Corresponding to boron energies of 2 and 4 keV. Implantation of 11 B was carried out at energies 6, 8 and 10 keV. All wafers were implanted with 5×10 15 cm −2 boron ions at 7° to the 〈100〉 axis of silicon. The concentration of boron as a function of depth below the silicon surface was measured using the 165 keV resonance of the 11 B(p, α) 8 Be ∗ nuclear reaction and a grazing incidence angle geometry of 10°. The concentration profiles are compared with reported ranges measured by other methods and are found to be in agreement. The results have shown that quantitative information about the profile at depths beyond the maximum concentration is difficult to extract because of the shape of the nuclear reaction resonance curve.