The diffusion of 30Si was measured along the c-axis of -phase quartz, at 1400 to 1600C, by using Rutherford back-scattering spectrometry and the 30Si(p,)31P resonant nuclear reaction. It was found that the diffusivity could be described by:

D (cm2/s) = 1.26 x 106 exp[-7.6(eV)/kT]

These values were comparable to the diffusivity of Si in vitreous SiO2. It was suggested that Frenkel pairs were the majority defects, and that diffusion occurred via an interstitial mechanism.

O.Jaoul, F.Béjina, F.Elie, F.Abel: Physical Review Letters, 1995, 74[11], 2038-41