Origin of anE3-like defect in GaAs andGaAs1−xSbxalloys

Energy level and concentration of $E3\mathrm{}$ defects produced by electron bombardment have been measured in various $\mathrm{Ga}{\mathrm{As}}_{1-x}{\mathrm{Sb}}_x$ alloys ($x=0\mathrm{} \mathrm{to} 0.2$). The average defect introduction rate reduces with decrease of the arsenic atom fraction suggesting that the defects are As-site related. The energy level of $E3\mathrm{}$ remains constant (∼ 1.0 eV) with respect to top of the valence band in these alloys. Results of theoretical calculations are presented which support the assignment of $E3\mathrm{}$ to a defect related to $V_{\mathrm{As}}$.