Atomic layer molecular beam epitaxy growth of GaAs1−xPx layers: Study of P2 incorporation by the reflectance difference technique

Abstract

A study of the P2 incorporation process onto the GaAs1−xPx(001) surface by the reflectance difference technique is presented. The growth technique is atomic layer molecular beam epitaxy (ALMBE), using successive pulses of P2 and As4 on a Ga rich intermediate surface. Experimental results on the dependence of the efficiency of phosphorus incorporation on P2 dosage and Ga surface coverage show that the saturation of P2 incorporation is limited by the Ga surface coverage and that the efficiency of phosphorus incorporation is larger for a Ga surface coverage above 0.12Ns, where Ns=6.25×1014 sites cm−2 for an ideal (001) surface. These results allow one to establish the appropriate experimental conditions to grow GaAs1−xPx layers by ALMBE with accurate control of the phosphorus content.