Photoluminescence study of GaAs implanted with 100MeV 28Si ions

Low temperature photoluminescence study of GaAs defect states*

“…The V As is a donor with energy level at 145 meV below the conduction band. [3,10,35] Since V As is a deep donor and Ga As is a deep acceptor, they are bound together by the Coulombic force to form a localized donor-acceptor pair, which acts as a stationary molecule. The characteristic of the localized deep centers is the strong coupling between the electronic state and the lattice.…”

“…[2] For this reason, the identification and characterization of defects in GaAs substrate, as well as the understanding of their optical and thermodynamical properties, are very important and remain an active research field. [3][4][5][6][7] There are six elementary native point defect species in GaAs substrate: vacancies in the Ga sublattice (V Ga ), vacancies in the As sublattice (V As ), Ga selfinterstitials (I Ga ), As self-interstitials (I As ), antisite defects formed by a Ga atom on an As site (Ga As ) and an As atom on a Ga site (As Ga ). [8] V As and Ga As are at E C − 0.145 eV and E V + 0.078 eV, respectively.…”

“…[9] The spectral features of these defects in the photoluminescence (PL) spectra of GaAs have been studied. [3,[10][11][12][13] PL is very sensitive to lattice perfection and has been extensively used to characterize the impurity and defect energy levels in GaAs. [14][15][16][17] The characterization of GaAs substrates is of great significance for improving the crystal growth quality of the epitaxial layers.…”