Segregation of antimony to Si/SiO2 interfaces

Segregation of n-type dopants to interfaces is an important contribution to the loss of electrical activity in current and future device generations. In this work, the segregation and pile-up of antimony atoms at the Si/SiO2 interface was investigated at a temperature of 1000 °C by a combination of gracing incidence X-ray fluorescence spectroscopy (GI-XRF) measurements, electrical measurements, and etching on the nanometer scale. Long annealing times were used to make sure that the segregated atoms are in steady state with the antimony atoms in the bulk. Assuming that the segregated atoms are electrically neutral, their sheet concentration can be modeled as steady state with positively charged substitutional antimony atoms and free electrons.