Assignment of EPR spectrum for bistable thermal donors in silicon

It has been shown that bistability of thermal double donors (TDD) in silico n can be observed by EPR technique. The spectrum of a bistable TDD species (TDD2) has been isolated using heat-treatment of Czochralsky-grown n-type s ilicon crystals with initial resistivity 4.5 Ohm cm, at temperature 400 deg rees C and subsequent irradiation with electrons (E = 3.5 MeV), The princip al values of the TDD2 g-tensor are determined as g(1) = 1.9928, g(2) = 2.00 09, g(3) = 1.9999. An interpretation of some EPR data is given in the frame work of the two-center model of the TDD structure. (C) 1999 Elsevier Scienc e B.V. All rights reserved.