The in-diffusion of B from borosilicate glass, using rapid thermal processing, was studied. It was found that the sheet resistance of diffused layers decreased more steeply than t-½ as a function of time, after short diffusion times and at low temperatures. This corresponded to a rapid increase in the surface B concentration in the initial stages of diffusion. This was attributed to the presence of thin native oxides between the borosilicate glass and the Si. The time that was required for the surface B concentration to saturate was shorter for borosilicate glass with higher B concentrations. The diffusion of B was enhanced when the B concentration in the borosilicate glass was greater than 18at%. An enhanced diffusivity was also observed when furnace annealing was used and the B concentration in the glass was greater than 18at%. It did not occur when the B concentration was 7at%. Enhanced diffusion was not observed during rapid thermal annealing if the glass was not used.

M.Miyake: Journal of the Electrochemical Society, 1991, 138[10], 3031-9