Structure of Si:Mn annealed under enhanced stress conditions
|Jadwiga Bak-Misiuk 1, Przemysław Romanowski 1, Elzbieta Dynowska 1, Artem Shalimov 1, Andrzej Misiuk 2, Slawomir Kret 1, Piotr Dłużewski 1, Adam Barcz 1,2, Jaroslaw Domagala 1, Wolfgang Caliebe 3, Jerzy Dąbrowski 1|
1. Polish Academy of Sciences, Institute of Physics, al. Lotników 32/46, Warszawa 02-668, Poland
Silicon implanted with Mn (Si:Mn) is magnetically ordered after appropriate annealing . This work concerns the Si:Mn structure as well as its dependence on temperature during implantation, Ts, and on subsequent annealing parameters.
Si:Mn was prepared by implantation of Czochralski silicon with 160 keV Mn+ ions at Ts = 340 K and 610 K to a dose 1x1016 cm-2. Si:Mn was processed at temperature, Ta, up to 1270 K for up to 10 h under ambient (105 Pa) and enhanced Ar hydrostatic pressure (HP, up to 1.2 GPa). Concentration profile of Mn was measured by SIMS; the defect structure was determined by high resolution X-Ray diffraction and diffraction in the grazing incidence geometry (synchrotron).
The near–surface area of Si:Mn implanted at Ts = 340 K is amorphous. In the case of implantation at Ts = 610 K, this area is better ordered, with well-defined layered structure, while the buried layer is polycrystalline. Subsequent annealing of Si:Mn results in re-crystallization of disturbed layer and formation of the Mn4Si7 phase (Fig. 1). These effects depend, among others, on Ts, Ta and HP. After processing at 1270 K, the samples implanted at Ts = 340 K indicated the presence of dislocation loops while vacancies and / or interstitials were formed in Si:Mn prepared at 610 K. The treatments under 105 Pa and under HP result, respectively, in the dominating presence of interstitials and vacancies.
Our results help to understand the origin of magnetic ordering in Si:Mn.
Fig. 1. Powder diffraction patterns in grazing incidence geometry for Si:Mn implanted at Ts = 340 K (a) and 610 K (b): 1 - as-implanted; 2 - annealed for 1 h at 610 K under 105 Pa; 3, 4 - annealed for 1 h at 870 K under 105 Pa and 1.1 GPa, respectively.
Presentation: Poster at E-MRS Fall Meeting 2007, Symposium H, by Przemysław Romanowski
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-08-03 13:15 Revised: 2009-06-07 00:44