Second harmonic microscopy was used to study In diffusion on (111) surfaces. It was found that, for homologous temperatures that were near to 0.5 and coverages ranging from 0 to 0.7, the In diffusivity (table 178) could be described by:

D (cm2/s) = 3000 exp[-42(kcal/mol)/RT]

The values of the Arrhenius parameters, which were quite large, were explained semi-quantitatively in terms of an adatom-vacancy model which had been developed for similar systems. The present work offered considerable evidence for the effects of adatom-vacancy ionization.

C.E.Allen, R.Ditchfield, E.G.Seebauer: Journal of Vacuum Science and Technology A, 1996, 14[1], 22-9

 

Table 178

Diffusivity of In on the (111) Surface of Si

 

 

Temperature (C)

D (cm2/s)

595

9.1 x 10-8

580

6.0 x 10-8

560

2.8 x 10-8

540

1.1 x 10-8

520

6.0 x 10-9

505

4.0 x 10-9

480

1.7 x 10-9

465

9.6 x 10-10