Electrically active centers in light emitting Si:Er/Si structures grown by the sublimation MBE method

Abstract

The electrically active centers in light-emitting Si:Er/Si structures grown by an original sublimation MBE (SMBE) method are investigated using admittance spectroscopy and deep level transient spectroscopy. It is shown that free carrier concentration in investigated structures is determined by shallow donors with ionization energies varying from 0.016 to 0.045eV. The essential difference between deep level defects observed in SMBE Si:Er/Si structures and in Si:Er/Si structures produced by ion implantation is revealed. The causes of observed distinctions between electrical and optical properties of SMBE structures as well as distinctions between SMBE and ion implanted Si:Er/Si structures are discussed. © 2001 Elsevier Science B.V. All rights reserved.