The dynamic behavior of α and β dislocations in undoped or impurity-doped crystals was investigated as a function of stress and temperature by using etch-pit techniques. A suppression of the generation of dislocations from a surface scratch was found in S-doped material and was explained in terms of dislocation locking due to impurity clusters and/or impurity-defect complexes; as observed in other III-V compounds. The α dislocations moved faster than β dislocations in undoped and impurity-doped material. The presence of S donors reduced the velocities of both types of dislocation. On the other hand, Zn acceptors increased the velocity of α dislocations and reduced the velocity of β dislocations. Such effects were attributed to the electronic state of the dislocations during the elementary processes of motion. The measured velocities could be expressed as simple empirical functions of stress and temperature. The linear dependence of the activation energy for dislocation motion, upon the band-gap energy, clearly depended upon the type of semiconductor (figure 5).

Dynamic behavior of dislocations in InAs I.Yonenaga: Journal of Applied Physics, 1998, 84[8], 4209-13

Figure 5

Activation Energy for Dislocation Motion,

as a Function of Band-Gap Energy

and Compound Type