The out-diffusion of O from Czochralski-type (100) wafers, when annealed at high temperatures under a H or Ar ambient, was investigated by means of secondary ion mass spectrometry. The wafers were annealed in 3 successive stages. These were the loading of wafers into a furnace at 850C, ramping up, annealing at 1200C for 1h, and ramping down to 850C. It was found that the O diffusivities which were found for the 2 ambients had almost the same values. No difference in the O concentration of the sub-surface region was observed for the 2 types of sample; within a detection limit of 2 x 1016 atoms/cm3.

Influence of Annealing Ambient on Oxygen Out-Diffusion in Czochralski Silicon H.Yamazaki, H.Matsushita, J.Sugamoto, N.Tsuchiya: Journal of Applied Physics, 2000, 87[9], 4194-7