Investigation of the temperature dependence of the acceptor center relaxation rate in silicon by the μ- SR-method

Results on the temperature dependence of the residual polarization of negative muons in silicon with phosphorus (3.2·1012, 2.3·1015 and 4.5·1018 cm-3) and aluminium (2·1014 and 2.4·1018 cm-3) impurities are presented. The measurements were carried out in a transverse to the direction of the muon spin magnetic field of 2000 Oe in the temperature range 4.2-300 K. The temperature dependence of the relaxation rate of the magnetic moment of the Al shallow acceptor centre in undeformed silicon is determined for the first time. The constant of the hyperfine interaction between the magnetic moment of the muon and that of the electron shell of the muonic atom (Ahf/2π ≅ 3·107 s-1) and the coefficient for capture of free electrons by a neutral aluminium atom in silicon (β(Al0) ≅ 7·10-14 cm3s-1 at 30 K) are estimated. (author)