Dislocation Nucleation and Propagation in Semiconductor Heterostructures

Authors

D. Cherns, University of BristolFollow
S. Mylonas, University of Bristol
C. T. Chou, University of Bristol
J. Wu, University of Bristol
D. E. Ashenford, University of Hull
B. Lunn, University of Hull

Abstract

This paper considers misfit dislocation nucleation and propagation in dilute magnetic semiconductor heterostructures in the CdTe-ZnTe-MnTe system. It is shown that, where the deposit is in tension, 1/2 < 110 > dislocations with inclined Burgers vectors propagate by glide along interfacial < 110 > directions and may dissociate giving intrinsic stacking faults. In cases where the deposit is in compression, 1/2 < 110 > dislocations show no evidence of dissociation and propagate by extensive cross-slip to give networks of dislocations close to interfacial < 100 > directions.

Evidence for dislocation sources in ZnTe/GaSb films is presented. ZnTe films contained stacking fault pyramids, single Frank faults and a new type of "diamond defect" are present at densities up to about 107 cm^-2. Analysis showed that the diamond defects, which were four-sided defects on {111} planes with < 110 > edges, were of vacancy type with 1/3 < 111 > Frank Burgers vectors and intrinsic stacking faults. Although faulted defects showed no tendency to grow by climb, evidence is given for an unfaulted reaction in which a glissile 1/2 < 110 > dislocation is generated. This new model for dislocation nucleation is discussed.

Recommended Citation

Cherns, D.; Mylonas, S.; Chou, C. T.; Wu, J.; Ashenford, D. E.; and Lunn, B. (1994) "Dislocation Nucleation and Propagation in Semiconductor Heterostructures," Scanning Microscopy: Vol. 8: No. 4, Article 10.
Available at: https://digitalcommons.usu.edu/microscopy/vol8/iss4/10