Diffusion of Boron into Silicon

Abstract

The boron diffusion into silicon has been investigated over a temperature range from 1100°C to 1300°C in a condition of constant source. True concentration profiles of boron diffusion layers were obtained by means of activation analysis by proton irradiations and conductivity measurements in order to understand the anomaly of apparent diffusion coefficient calculated from usual p-n junction method. In the case of low surface concentration less than 6×10¹⁹/cc, the boron distributions are represented as error function complement, whereas at higher surface concentrations they show more convex distribution. The fast diffusivity in the high concentration region is attributed to the enhanced diffusion by induced lattice strain.