A new antimony diffusion process using spin‐on doped oxide source was characterized and developed. Diffusion is enhanced in dilute oxidizing ambient due to increased surface concentration while diffusivity remains essentially the same in both nitrogen and dilute oxidizing ambient. Wright etch reveals no diffusion induced dislocation when surface concentration is less than . The thinner and less concentrated glass diffused in lower oxygen concentration ambient is less prone to glass devitrification. This process was proven to be suitable for buried layer formation in the fabrication of bipolar integrated circuits.