Substitution of InP layers to InAs for strain compensation in GaxIn1-xAs/InP superlattices

In this study controlled substitution of P by As atoms, by exposing an InP surface to cracked arsine, is demonstrated to form thin InAs layers, All-structures have been grown by chemical beam epitaxy, The effect of the exposure time has been investigated in InAs single and multiple quantum wells. Characterisation was performed by X-ray diffraction and photoluminescence spectroscopy. A two-stage substitution process is concluded. During the fast first stage the top P layer is exchanged by As. Longer exposure times lead to the complete substitution of the P layer underneath. In the mean time a three-dimensional rearrangement results in the formation of InAs islands, These thin compressed InAs layers have successfully been used for strain compensation in GaxIn1-xAs/InP superlattice structures.