DEPTH DISTRIBUTION OF DIVACANCIES IN 400-keV O+ ION-IMPLANTED SILICON

The integral depth distribution for divacancies produced in silicon at room temperature by 400-keV O+ion implantation has been measured. The divacancy distribution was determined from repeated measurements of the characteristic 1. 8μ absorption band following successive anodizations and strippings of the implanted layer. Most of the divacancies are located between 4500 and 12 000 Å with a half-value at ∼ 7500 Å and a concentration of ∼ 4 × 1019 cm−3 near the center of the distribution. The measured integral depth distribution for the ion-produced divacancies is proportional within experimental error to theoretical calculations by Brice for the integral depth distribution of ion energy spent in atomic processes.