This article is cited in 2 papers

Electronic properties of semiconductors

Investigation of energy levels of Er-impurity centers in Si by the method of ballistic electron emission spectroscopy

D. O. Filatov^a, I. A. Zimovets^b, M. A. Isakov^a, V. P. Kuznetsov^a, A. V. Kornaukhov<sup>a

a</sup> Scientific-Research Physicotechnical Institute at the Nizhnii Novgorod State University, Nizhnii Novgorod
^b National Research Lobachevsky State University of Nizhny Novgorod

Abstract: The method of ballistic electron emission spectroscopy is used for the first time to study the energy spectrum of Er-impurity complexes in Si. The features are observed in the ballistic electron spectra of mesa diodes based on $p^+$–$n^+$ Si structures with a thin ($\sim$30 nm) $p^+$-Si:Er surface layer in the region of ballistic-electron energies eV t lower than the conduction-band-edge energy $E_c$ in this layer. They are associated with the tunnel injection of ballistic electrons from the probe of the scanning tunnel microscope to the deep donor levels of the Er-impurity complexes in the $p^+$-Si:Er layer with subsequent thermal excitation into the conduction band and the diffusion to the $p^+$–$n^+$ junction and the direct tunneling in it. To verify this assumption, the ballistic-electron transport was simulated in the system of the Pt probe, native-oxide layer SiO$_2$-$p^+$-Si : Er-$n^+$, and Si substrate. By approximating the experimental ballistic-electron spectra with the modeling spectra, the ground-state energy of the Er complex in Si was determined: $E_d\approx E_c$ – 0.27 eV. The indicated value is consistent with the data published previously and obtained from the measurements of the temperature dependence of the free-carrier concentration in Si:Er layers.

Received: 07.02.2011
Accepted: 14.02.2011

 English version: Semiconductors, 2011, 45:9, 1111–1116

Bibliographic databases:

•