Electrical activation of silicon implanted in semihyphen;insulating GaAs: Role of boron and the midgap electron trap (EL2)

摘要

A model based on the constraint of stoichiometry is developed to account for some existing data on the donor activation of silicon ions implanted in semihyphen;insulating, boronhyphen;doped GaAs grown by the liquid encapsulated Czochralski method. As a function of increasing implant dose (up to 1013ions/cm2), three stages of activation are pictured: facilitation by EL2, inhibition by boron, and finally, 100percnt; differential activation when boron is depleted. Possible atomic structures are suggested for the boronhyphen;related defects and siliconhyphen;related donors. A proposal for using implant measurements to help establish the atomic structure of EL2 is advanced.