A method for the determination of diffusion coefficients from carrier concentration depth profiles is presented. Carrier profiles created during diffusion from ion‐implanted sources were determined by differential conductivity measurements. The experimentally obtained distribution has been fitted for each sample by a smooth spline function approximation. Then applying the modified version of the Boltzmann transformation, diffusion coefficients of boron, phosphorus, and arsenic in silicon were determined. A full agreement between the measured and the calculated distribution was obtained when the concentration‐dependent diffusion coefficient was inserted into the numerical solution of the diffusion equation. The temperature dependence of the diffusion coefficient of boron was also calculated and the activation energy value
Enormala=3.31 normaleV
was obtained.