Amphoteric native defect reactions in Si-doped GaAs

Abstract

Strong evidence for amphoteric native defect reactions is obtained by photoluminescence analysis of Si-doped GaAs samples (n≈1.5×1018 cm−3) annealed under different conditions. Annealing in excess As4 vapor creates a large concentration of Ga vacancies, making possible the transformation of this defect into an As vacancy and an As antisite defect. Similarly, As vacancies generated at high concentration during annealing under Ga-rich conditions are transformed into Ga vacancies and Ga antisite defects. Photoluminescence intensities associated with the corresponding defects are in qualitative agreement with the predictions of the mass action law applied to the amphoteric native defect reactions.

Defect distribution in boron-reduced GaAs crystals grown by vapour-pressure-controlled Czochralski technique

“…Beyond an electron concentration of about 1 Â 10 18 cm À3 the former one vanishes completely. In contradiction to the results published so far [17][18][19][20][21], we assign the 0.95 eV band to the (V Ga Si Ga ) 2À and the 1.15 eV transition to the (Si Ga V Ga Si Ga ) À complex. Detailed arguments will be published elsewhere [34].…”

“…Studies on the influence of boron on vacancy concentrations show that boron decreases the concentration of Ga vacancies (V Ga ) [15,16]. Isolated vacancies form (donor-V Ga ) complexes due to Coulomb interaction and its concentration relates to the intensity of luminescence bands at 0.95 and 1.15 eV [17][18][19][20][21]. In this study, we present experimental data on the dependence of the formation of these compensating (donor-V Ga ) complexes on Si doping.…”

Photoluminescence of Be implanted Si-doped GaAs

“…The peak position was independent of the incident intensity, and the peak height was proportional to the incident intensity. Ky et al 24 reported a peak between 1.45 eV and 1.47 eV in Si-doped GaAs (n = 1-8 × 10 18 cm -3 ) at 80 K. If 11 meV is added to these energies to compensate for the difference in temperature and thus bandgap, 21 the peak positions are seen to correspond. Ky et al 24 attributed the peak to transitions of free electrons to Ga As antisite acceptor defects, with an ionization energy of 68-77 meV.…”

<title>Formation of low energy tails in silicon δ-doped GaAs/AlAs multiple quantum wells</title>

“…Six elementary native point defect species exist in GaAs: vacancies in the Ga sublattice (V Ga ), vacancies in the As sublattice (V As ), Ga self-interstitials, As selfinterstitials, and antisite defects formed by a Ga atom on an As site (Ga As ) or an As atom on Ga site (As Ga ). 19 Amongst the six intrinsic defects of GaAs, only V Ga and Ga As are acceptors. 20 For Si doped GaAs, it has been found that Si can behave as donor Si Ga , an acceptor Si As and form Si pairs, clusters and complexes of Si atoms with native defects 12 , which together can be responsible for self compensation mechanisms and creation of energy levels in the forbidden energy gap.…”