The diffusion of donor elements in fine-grained and coarse-grained polycrystalline material was studied at temperatures ranging from 900 to 1150C. Tracers (32P) were used to determine the concentration/depth profiles via sectioning. By means of autoradiography, the lateral distribution of the radiotracers over the sample surface was revealed. The grain boundary diffusivity (table 91) could be described by:

D (cm2/s) = 1.2 x 102exp[-2.87(eV)/kT]

Diffusion of Donor Elements (125Sb, 82P, 74(73)As) in Polycrystalline Silicon. F.H.M.Spit, H.Bakker: Physica Status Solidi A, 1986, 97[1], 135-42

 

Table 91

Grain Boundary Diffusion of P in Si

 

Temperature (C)

D (cm2/s)

1150

6.9 x 10-9

1100

3.9 x 10-9

1050

1.4 x 10-9

1000

4.7 x 10-10

950

2.2 x 10-10

900

4.0 x 10-11