J. Phys. I France
Volume 1, Numéro 10, October 1991
Page(s) 1511 - 1527
DOI: 10.1051/jp1:1991223
J. Phys. I France 1 (1991) 1511-1527

The EL2 center in GaAs: symmetry and metastability

N. T. Bagraev

A. F. Ioffe Physico-Technical Institute, Academy of Sciences of the USSR, Leningrad 194021, U.S.S.R.

(Received 22 May 1991, accepted I2 June 1991)

Photo-EPR, piezospectroscopic and Stark-effect photocapacitance data were used to determine the symmetry of the EL2 center in GaAs and to identify the mechanism that underlies its metastable behavior. The results unambiguously point to C $_{\rm {3V}}$ as the type of symmetry for this antisite double donor whose charge states - D + = As Ga, D 0= (As $_{\rm i}$V $_{\rm Ga}$) 0 and D ++ = (As $_{\rm i}$V $_{\rm Ga}$) ++ - occupying, respectively, the positions on the site and in the tetrahedral and hexagonal interstices, are brought about, in the same order, by the wavefunctions of the $\Gamma$, L and X valleys of the conduction band. The transition made by the EL2 center to a metastable state is the result of a charge exchange of the type 2D + + $hv \rightarrow$ D 0 + D ++ , which causes the antisite As, defect to tunnel from its position at the site to a position in the tetrahedral interstice. Annealing of the center in this state proceeds at such temperatures and rates as are determined by the height of the energy barrier to the D 0 + $h \rightarrow$ D + reaction.

© Les Editions de Physique 1991

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.