A measurement of N out-diffusion from N-doped float-zone Si made using a dislocation locking technique was presented. Specimens containing a well-defined array of dislocation half-loops were subjected to identical anneals at 750C, during which N diffused both to the surface and to the dislocations. The specimens were then chemically etched so as to remove various thicknesses of material from the surface. The stress required to move the dislocations away from the N was then measured. The variation in this unlocking stress with thickness of material removed permitted the N diffusivity to be deduced. The results obtained were consistent with the extrapolation of secondary ion mass spectrometry out-diffusion measurements previously performed at higher temperatures, but indicated a different activation energy for out-diffusion to that associated with dislocation locking by N.

Out-Diffusion of Nitrogen from Float-Zone Silicon Measured by Dislocation Locking. C.R.Alpass, J.D.Murphy, A.Giannattasio, S.Senkader, R.J.Falster, P.R.Wilshaw: Physica Status Solidi A, 2007, 204[7], 2256-60