The effects of In impurity on the dynamic behavior of dislocations in GaAs crystals are investigated in comparison with those of Si impurity. Indium, even at a concentration of the order of 1020 cm -3, is found to affect the velocity of moving dislocations only slightly while Si impurity at a concentration of the order of 10 18 cm-3 reduces it by one or two orders of magnitude. However, α dislocations are easily immobilized by In atoms while they are at rest by gettering the latter. Immobilization of β dislocations due to In gettering is much weaker than that of α dislocations. An interpretation is given of how such a difference in locking by In impurity comes about between α and β dislocations. The function of Si impurity to lock both α and β dislocations is stronger than that of In impurity on α dislocations. Nevertheless, the locking effect due to Si impurity manifests itself only in the high-temperature range. This seems to be related to the low diffusivity of Si impurity in GaAs crystals.
ASJC Scopus subject areas
- Physics and Astronomy(all)