Dislocation nucleation mechanism and doping effect in p-type ZnSe/GaAs
- Univ. of Maryland, College Park, MD (United States)
- 3M Company, St. Paul, MN (United States); and others
Nitrogen doped ZnSe/GaAs heterostructures grown at 150 and 250{degrees}C were studied by transmission electron microscopy (TEM). The density of threading dislocations and the interfacial dislocation structure in ZnSe/GaAs heterostructures are related to the N-doping concentration. In addition, in-situ TEM heating studies show that Frank partial dislocations formed below critical thickness in N-doped ZnSe/GaAs are the sources for nucleation of a regular array of misfit dislocations at the ZnSe/GaAs interface. By the dissociation of the Frank partial dislocations and interaction reactions between the dislocations, the 600 misfit dislocations form. The Frank partial dislocations bound stacking faults which usually form in pairs at the film/substrate interface. The density of stacking faults increases with increasing N-doping concentration. Thus, at high N-doping levels, the dislocation nucleation sources are close together and not all of the Frank partial dislocations dissociate, so that a high density of threading dislocations results in samples with high N-doping concentrations. The high density of threading dislocations in the ZnSe film are found to be associated with a reduction or saturation of the net carrier density. 9 refs., 6 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 478437
- Journal Information:
- Journal of Electronic Materials, Journal Name: Journal of Electronic Materials Journal Issue: 3 Vol. 23; ISSN JECMA5; ISSN 0361-5235
- Country of Publication:
- United States
- Language:
- English
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