The geometric structures of the GaAs(111) and (110) surfaces

Abstract

We present results of a reconstruction model proposed for the (2×2) GaAs(111) surface, together with a reexamination of the (1×1) GaAs(110) surface structure. Our model indicates that the reconstruction mechanisms on the (111) and (110) surfaces are similar to one another. In both cases, surface electronic energies are lowered via orbital rehybridization between nearest neighbor Ga and As atoms with dangling bonds. Reexamination of the GaAs(110) surface structure confirms our previous result of a tilt angle of ω=27°±2° and rejects a recently proposed value of ω=7°.