CHANNELING STUDY OF BORON-IMPLANTED SILICON

Abstract

The channeling technique has been used to determine the lattice location of boron implanted into silicon by using the B¹¹ (p,α) nuclear reaction. Approximately 30% of the boron lies on substitutional sites after a room‐temperature implantation of 3×10¹⁵/cm². The substitutional content decreases with annealing temperature up to 700 °C and then increases at higher annealing temperature. This explains a reverse annealing behavior observed in the carrier concentration. Nearly all of the boron lies on substitutional sites after annealing at 1100 °C. The nonsubstitutional boron atoms do not occupy the normal tetrahedral interstitial sites. For annealing temperatures up to 500 °C they appear to lie along atomic rows, but they do not lie midway between row lattice sites. After higher‐temperature annealing their location appears less well‐defined.