title: E center in silicon has a donor level in the band gap.
abstract: It has been an accepted fact for more than 40 years that the E center in Si (the group-V impurity--vacancy pair)--one of the most studied defects in semiconductors--has only one energy level in the band gap: namely, the acceptor level at about 0.45 eV below the conduction band. We now demonstrate that it has a second level, situated in the lower half of the band gap at 0.27 eV above the valence band. The existence of this level, having a donor character, is disclosed by a combination of different transient-capacitance techniques and electronic-structure calculations. The finding seriously questions some diffusion-modeling approaches performed in the past.
authors.affiliation: Institute of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark.
authors.forename: A Nylandsted
authors.initials: AN
authors.lastname: Larsen
authors.forename: A
authors.initials: A
authors.lastname: Mesli
authors.forename: K Bonde
authors.initials: KB
authors.lastname: Nielsen
authors.forename: H Kortegaard
authors.initials: HK
authors.lastname: Nielsen
authors.forename: L
authors.initials: L
authors.lastname: Dobaczewski
authors.forename: J
authors.initials: J
authors.lastname: Adey
authors.forename: R
authors.initials: R
authors.lastname: Jones
authors.forename: D W
authors.initials: DW
authors.lastname: Palmer
authors.forename: P R
authors.initials: PR
authors.lastname: Briddon
authors.forename: S
authors.initials: S
authors.lastname: Oberg