Enhanced Diffusion of High-Temperature Ion-Implanted Antimony Into Silicon

Concentration profiles of 20-keV high-temperature ion-implanted antimony into a silicon single crystal were measured by means of radioactivation analysis and the enhanced diffusion was observed. The concentration profiles were found to be independent of temperature over the range between 500 °C and 800 °C and to be dependent on the dose rate of ion implantation. The diffusion coefficient of antimony is estimated to be about 1.1×10−15 cm2/sec for the dose rate of about 1.2×1012 ions/cm2 sec and about 6.6×10−15 cm2/sec for that of about 7.2×1012 ions/cm2 sec. The measured concentration profiles are in good agreement with the calculated concentration profile. These results are explained on the basis of a vacancy mechanism.