Desorption of the Excess Gallium Atoms at the Surface of Gallium Arsenide and Application to Atomic Layer Epitaxy

Desorption of the excess gallium atoms at the gallium arsenide surface is studied by means of an alternating source supply method. The activation energy of the desorption is estimated to be 2.5 eV, which is substantially smaller than that of the sublimation of Ga atoms from GaAs crystal (4.9 eV). Using this desorption behavior, the possibility of atomic layer epitaxy by molecular beam epitaxy is examined.