Competition between Long-Living and D?(A+) States of Donors and Acceptors in Silicon
Ya. E. Pokrovskiı̆, Igor V. Altukhov, O.I. Smirnova, N. A. Khval’kovskii · physica status solidi (b) · 1998
The photoconductivity (PC) spectra and the induced absorption of background radiation in the energy range 10 to 40 meV are investigated in relatively low compensated B-, Ga- and As-doped Si at 4.2 K. Dips, corresponding to the photoionization of long-living excited states of B and As, are observed in the PC spectra of the D−(A+) bands. It was found, that PC of the bands has a slow relaxation (≈︂10−4 s). So, the localization of nonequilibrium carriers in long-living excited states of B and As and in the D−(A+) states leads to a competition of both slow relaxation processes in PC and absorption phenomena. The separation of the processes is possible in electric field. It leads to a decrease of PC due to D−(A+) states but weakly influences the long-living excited states absorption.