The effect of an ultrasonic treatment (UST) in various regimes (f UST = 4−30MHz; W UST = 0.1−2W/cm2) on the electrical activity of radiation defects in γ-irradiated (D = 108 and 109 rad) n-type Si crystals doped with oxygen (∼1018 and <5 x 1015/cm3) was studied. The energies and concentrations of the electrically active centres were determined from an analysis of the temperature dependence (100−300K) of the Hall effect characteristics, assuming a multilevel structure for these centres. The main types of the acoustically active defects, which change the properties of the semiconductor material upon UST, were the A-type centres (Ec-0.20eV) and divacancies (Ec-0.26eV) in Czochralski-grown single crystals and the divacancies and/or Ps−Ci complexes (Ec-0.23eV) in float-zone samples.

Acoustic-Wave-Stimulated Transformations of Radiation Defects in γ-Irradiated n-Type Silicon Crystals. Y.M.Olikh, M.D.Tymochko, A.P.Dolgolenko: Technical Physics Letters, 2006, 32[7], 586-9