The effect of thin film thickness on the incorporation of Mn interstitials in Ga{sub 1-x}Mn{sub x}As
We have investigated the effect of film thickness on the distribution of Mn atoms at various lattice sites in Ga{sub 1-x}Mn{sub x}As thin films. We find that the growth surface acts as a sink facilitating the out-diffusion of Mn interstitials (Mn{sub I}), and thus reducing its concentration in the film. The out-diffused Mn{sub I} accumulate on the surface in a surface oxide layer and do not participate in the ferromagnetism of the film. For thin films less than 15 nm thick, no Mn{sub I} can be detected. Because of the absence of compensating Mn{sub I} defects, higher T{sub C} can be achieved for such extremely thin Ga{sub 1-x}Mn{sub x}As layers. These results agree with our previously suggested Fermi-level-governed upper limit of the T{sub C} of III-Mn-V ferromagnetic semiconductors.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of Basic Energy Sciences. Materials Science and Engineering Division; National Science Foundation Grant DMR02-10519, Department of Defense. Defense Advanced Research Projects Agency. SpinS Program (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 842113
- Report Number(s):
- LBNL-56437; R&D Project: 513320; TRN: US200515%%1101
- Journal Information:
- Applied Physics Letters, Vol. 86; Other Information: Submitted to Applied Physics Letters: Volume 86; Journal Publication Date: 2005; PBD: 5 Oct 2004
- Country of Publication:
- United States
- Language:
- English
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