Auger de-excitation of different Er centers in Si:Er layers grown with sublimation molecular beam epitaxy

摘要

The Auger de-excitation of erbium ions in sublimation molecular beam epitaxy (SMBE) grown Si:Er/Si layers differing in the type of Er centers is investigated. In layers with the precipitate-like emitting centers (T_(gr)～ 500 ℃) the Auger de-excitation of Er~(3+) ions depends on the ionization of donors with the ionization energy E_i ~ 38 meV and a concentration of about 1 • 10~(16) cm~(-3), whereas in layers with the Er-Ol centers (T_(gr) ～ 400 ℃) it is determined by the ionization of donors having a lower ionization energy E_i ~ 20 meV and a higher concentration of ～2 • 10~(17) cm~(-3). It is shown that the compensation ratio of SMBE grown n-Si:Er layers with the precipitate-like emitting centers reaches 10% and more. The nature of the compensating impurity has not been identified.