A systematic investigation was made, of the diffusion of acceptor impurities (Rb, As) and of host or iso-electronic elements (Se, Te, Cd), by means of radio-tracer techniques; combined with non-stoichiometric annealing conditions (table 11). The diffusion coefficients of the host atoms, as well as of dopants which preferred to occupy the metal or chalcogen sub-lattice, exhibited a clear tendency to be enhanced if the necessary lattice sites for dopant incorporation were not provided. This was interpreted as being interstitial diffusion. Under optimum conditions, the dopants were incorporated at lattice sites and diffusion was hindered.

Investigations on Self-Diffusion and Diffusion of Dopants in II-VI Semiconductor Compounds Depending on its Non-Stoichiometry M.Wienecke, B.Reinhold, S.Hermann: Journal of Crystal Growth, 1999, 204[4], 441-6

 

 

Table 11

Diffusivities of Various Dopants in ZnSe

 

Dopant

Condition

Temperature (C)

D (cm2/s)

Se

metal saturation

900

5.5 x 10-13

Se

chalcogen saturation

900

9.0 x 10-13

Te

metal saturation

600

1.0 x 10-14

Te

chalcogen saturation

600

2.0 x 10-13

As

metal saturation

600

1.3 x 10-14

As

chalcogen saturation

600

2.1 x 10-13

Rb

metal saturation

600

1.3 x 10-12

Rb

chalcogen saturation

600

2.7 x 10-13