Diffusion processes of boron, phosphorus, and arsenic into silicon have been investigated using a new diffusion source called "spin-on source". Diffusion coefficients of these impurities have been calculated from the experimental results and are compared with the published values. Reasonable agreements have been found between the calculated and the published values. From this study, it is concluded that the spin-on source can be used as the diffusion source for integrated circuit fabricaticon.ricaticon.