Dislocation formation mechanism in strained {ital In}{sub {ital x}}Ga{sub 1{minus}{ital x}}As islands grown on GaAs(001) substrates
- Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)
- Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (United States)
The formation mechanism of misfit dislocations in lattice-mismatched {ital In}{sub {ital x}}Ga{sub 1{minus}{ital x}}As epilayers (0.2{le}{ital x}{le}1) grown on GaAs substrates has been investigated experimentally. The results suggest that 1/3{l_angle}111{r_angle} Frank partial dislocations are grown-in at island edges in highly lattice-mismatched epilayers ({ital x}{ge}0.4). Then after further island growth 90{degree} Shockley partial dislocations are nucleated to remove the stacking faults, reacting with the Frank partials to form complete 90{degree} dislocations. An atomic model is proposed to explain the formation mechanism of the Frank partial dislocation. This model could explain the observed change in the dominant type of dislocation from the 60{degree} at small mismatches to 90{degree} edge dislocations at large lattice mismatches. {copyright} {ital 1996 American Institute of Physics.}
- Research Organization:
- Lawrence Berkeley National Laboratory
- DOE Contract Number:
- AC03-76SF00098; AC04-94AL85000
- OSTI ID:
- 277114
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 1 Vol. 68; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Variation of dislocation morphology with strain in Ge sub x Si sub 1 minus x epilayers on (100)Si
Nucleation of misfit and threading dislocations in GaSb/GaAs(001) heterostructure